Table of Contents
- VMG3312-T20A
- User’s Guide
- Introducing the VMG
- The Web Configurator
- Quick Start
- Tutorials
- 4.1 Overview
- 4.2 Setting Up an ADSL PPPoE Connection
- 4.3 Setting Up a Secure Wireless Network
- 4.4 Setting Up Multiple Wireless Groups
- 4.5 Using the File Sharing Feature
- 4.6 Using the Media Server Feature
- 4.7 Configuring Static Route for Routing to Another Network
- 4.8 Configuring QoS Queue and Class Setup
- 4.9 Access the VMG Using DDNS
- 4.10 Configuring the MAC Address Filter
- 4.11 Access Your Shared Files From a Computer
- Technical Reference
- Network Map and Status Screens
- Broadband
- Wireless
- Home Networking
- Routing
- Quality of Service (QoS)
- Network Address Translation (NAT)
- Dynamic DNS Setup
- Interface Grouping
- USB Service
- Firewall
- MAC Filter
- Parental Control
- Scheduler Rule
- Certificates
- Log
- Traffic Status
- ARP Table
- Routing Table
- xDSL Statistics
- Cellular Statistics
- System
- User Account
- Remote Management
- SNMP
- Time Settings
- E-mail Notification
- Logs Setting
- Firmware Upgrade
- Backup/Restore
- Diagnostic
- Troubleshooting
- Appendices
Zyxel VMG3312-T20A User Manual
Displayed below is the user manual for VMG3312-T20A by Zyxel which is a product in the Gateways/Controllers category. This manual has pages.
Related Manuals
Default Login Details
User’s Guide
VMG3312-T20A
Wireless N VDSL2 Combo WAN Gateway with USB
Copyright © 2017 Zyxel Communications Corporation
LAN IP Address http://192.168.1.1
Login admin, user
Password 1234, user
Version 5.30 Edition 1, 03/2017
VMG3312-T20A User’s Guide
2
IMPORTANT!
READ CAREFULLY BEFORE USE.
KEEP THIS GUIDE FOR FUTURE REFERENCE.
This is a User’s Guide for a system managing a series of products. Not all products support all features.
Menushots and graphics in this book may differ slightly from what you see due to differences in release
versions or your computer operating system. Every effort has been made to ensure that the information
in this manual is accurate.
Related Documentation
•Quick Start Guide
The Quick Start Guide shows how to connect the managed device.
•More Information
Go to support.zyxel.com to find other information on the VMG.
Contents Overview
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Contents Overview
User’s Guide ......................................................................................................................................14
Introducing the VMG ........................................................................................................................... 15
The Web Configurator ......................................................................................................................... 26
Quick Start ............................................................................................................................................. 33
Tutorials .................................................................................................................................................. 36
Technical Reference ........................................................................................................................65
Network Map and Status Screens ...................................................................................................... 66
Broadband ............................................................................................................................................ 70
Wireless ................................................................................................................................................... 96
Home Networking ............................................................................................................................... 123
Routing ................................................................................................................................................. 138
Quality of Service (QoS) .................................................................................................................... 145
Network Address Translation (NAT) ................................................................................................... 163
Dynamic DNS Setup ........................................................................................................................... 179
Interface Grouping ............................................................................................................................ 183
USB Service .......................................................................................................................................... 188
Firewall ................................................................................................................................................. 193
MAC Filter ............................................................................................................................................ 200
Parental Control ................................................................................................................................. 202
Scheduler Rule .................................................................................................................................... 207
Certificates .......................................................................................................................................... 209
Log ....................................................................................................................................................... 216
Traffic Status ....................................................................................................................................... 219
ARP Table ............................................................................................................................................ 222
Routing Table ...................................................................................................................................... 224
xDSL Statistics ....................................................................................................................................... 226
Cellular Statistics ................................................................................................................................ 228
System .................................................................................................................................................. 230
User Account ...................................................................................................................................... 231
Remote Management ....................................................................................................................... 234
SNMP .................................................................................................................................................... 237
Time Settings ........................................................................................................................................ 239
E-mail Notification .............................................................................................................................. 241
Logs Setting ........................................................................................................................................ 243
Firmware Upgrade .............................................................................................................................. 246
Backup/Restore .................................................................................................................................. 248
Diagnostic ........................................................................................................................................... 251
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Troubleshooting .................................................................................................................................. 253
Appendices .....................................................................................................................................259
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Table of Contents
Contents Overview .............................................................................................................................3
Table of Contents.................................................................................................................................5
Part I: User’s Guide..........................................................................................14
Chapter 1
Introducing the VMG...................................... ... .... .... ....................................................... .................15
1.1 Overview ......................................................................................................................................... 15
1.2 Ways to Manage the VMG ........................................................................................................... 15
1.3 Good Habits for Managing the VMG .......................................................................................... 15
1.4 Applications for the VMG ............................................................................................................. 16
1.4.1 Internet Access ...................................................................................................................... 16
1.4.2 VMG’s USB Support ............................................................................................................... 17
1.5 Wireless Access ............................................................................................................................... 19
1.6 Hardware ......................................................................................................................................... 19
1.6.1 Front Panel ............................................................................................................................. 19
1.6.2 LEDs (Lights) ........................................................................................................................... 20
1.6.3 Side Panels ............................................................................................................................. 21
1.6.4 Using the Wi-Fi and WPS Buttons ..........................................................................................23
1.6.5 Rear Panel .............................................................................................................................. 23
1.6.6 The RESET Button .................................................................................................................... 24
1.6.7 Wall Mounting ....................................................................................................................... 24
Chapter 2
The Web Configurator........................................................................................................................26
2.1 Overview ......................................................................................................................................... 26
2.1.1 Accessing the Web Configurator ....................................................................................... 26
2.2 Web Configurator Layout .............................................................................................................. 28
2.2.1 Title Bar ................................................................................................................................... 28
2.2.2 Main Window ......................................................................................................................... 28
2.2.3 Navigation Panel .................................................................................................................. 29
Chapter 3
Quick Start..........................................................................................................................................33
3.1 Overview ......................................................................................................................................... 33
3.2 Quick Start Setup ............................................................................................................................ 33
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Chapter 4
Tutorials ...............................................................................................................................................36
4.1 Overview ......................................................................................................................................... 36
4.2 Setting Up an ADSL PPPoE Connection ....................................................................................... 36
4.3 Setting Up a Secure Wireless Network .......................................................................................... 39
4.3.1 Configuring the Wireless Network Settings ......................................................................... 39
4.3.2 Using WPS ............................................................................................................................... 41
4.3.3 Without WPS ........................................................................................................................... 44
4.4 Setting Up Multiple Wireless Groups ............................................................................................. 44
4.5 Using the File Sharing Feature ....................................................................................................... 48
4.5.1 Set Up File Sharing ................................................................................................................. 48
4.5.2 Access Your Shared Files From a Computer ...................................................................... 51
4.6 Using the Media Server Feature .................................................................................................... 51
4.6.1 Configuring the VMG ........................................................................................................... 52
4.6.2 Using Windows Media Player ...............................................................................................52
4.6.3 Using a Digital Media Adapter ............................................................................................54
4.7 Configuring Static Route for Routing to Another Network ........................................................ 55
4.8 Configuring QoS Queue and Class Setup ................................................................................... 58
4.9 Access the VMG Using DDNS ........................................................................................................ 61
4.9.1 Registering a DDNS Account on www.dyndns.org ........................................................... 61
4.9.2 Configuring DDNS on Your VMG ......................................................................................... 61
4.9.3 Testing the DDNS Setting ...................................................................................................... 62
4.10 Configuring the MAC Address Filter ........................................................................................... 62
4.11 Access Your Shared Files From a Computer ............................................................................. 63
Part II: Technical Reference...........................................................................65
Chapter 5
Network Map and Status Screens ....................................................................................................66
5.1 Overview ......................................................................................................................................... 66
5.2 The Network Map Screen .............................................................................................................. 66
5.3 The Status Screen ........................................................................................................................... 67
Chapter 6
Broadband..........................................................................................................................................70
6.1 Overview ......................................................................................................................................... 70
6.1.1 What You Can Do in this Chapter ....................................................................................... 70
6.1.2 What You Need to Know ..................................................................................................... 71
6.1.3 Before You Begin ................................................................................................................... 74
6.2 The Broadband Screen .................................................................................................................. 74
6.2.1 Add/Edit Internet Connection .............................................................................................75
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6.3 The Cellular Backup Screen .......................................................................................................... 83
6.4 The Advanced Screen ................................................................................................................... 89
6.5 Technical Reference ...................................................................................................................... 91
Chapter 7
Wireless ...............................................................................................................................................96
7.1 Overview ......................................................................................................................................... 96
7.1.1 What You Can Do in this Chapter ....................................................................................... 96
7.1.2 What You Need to Know ..................................................................................................... 96
7.2 The General Screen ...................................................................................................................... 97
7.2.1 No Security ............................................................................................................................. 98
7.2.2 Basic (WEP Encryption) ......................................................................................................... 99
7.2.3 More Secure (WPA(2)-PSK) ................................................................................................ 100
7.3 The Guest/More AP Screen ......................................................................................................... 101
7.3.1 Edit Guest/More AP ........................................................................................................... 102
7.4 The MAC Authentication Screen ................................................................................................ 104
7.5 The WPS Screen ............................................................................................................................ 105
7.6 The WMM Screen .......................................................................................................................... 107
7.7 The Others Screen ........................................................................................................................ 108
7.8 The Channel Status Screen ......................................................................................................... 109
7.9 Technical Reference .................................................................................................................... 110
7.9.1 Wireless Network Overview ................................................................................................110
7.9.2 Additional Wireless Terms ................................................................................................... 112
7.9.3 Wireless Security Overview ................................................................................................. 112
7.9.4 Signal Problems ................................................................................................................... 114
7.9.5 BSS ......................................................................................................................................... 115
7.9.6 MBSSID .................................................................................................................................. 115
7.9.7 Preamble Type .................................................................................................................... 116
7.9.8 WiFi Protected Setup (WPS) ...............................................................................................116
Chapter 8
Home Networking............................................................................................................................123
8.1 Overview ....................................................................................................................................... 123
8.1.1 What You Can Do in this Chapter ..................................................................................... 123
8.1.2 What You Need To Know ................................................................................................... 124
8.1.3 Before You Begin ................................................................................................................. 125
8.2 The LAN Setup Screen .................................................................................................................. 125
8.3 The Static DHCP Screen ............................................................................................................... 129
8.4 The UPnP Screen ........................................................................................................................... 130
8.4.1 Turning On UPnP in Windows 7 Example .......................................................................... 131
8.5 The Additional Subnet Screen ..................................................................................................... 133
8.6 The STB Vendor ID Screen ............................................................................................................ 134
8.7 The Wake on LAN Screen ............................................................................................................ 134
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8.8 The TFTP Server Name Screen ..................................................................................................... 135
8.9 Technical Reference .................................................................................................................... 135
8.9.1 LANs, WANs and the VMG ................................................................................................. 135
8.9.2 DHCP Setup ......................................................................................................................... 136
8.9.3 DNS Server Addresses ......................................................................................................... 136
8.9.4 LAN TCP/IP ........................................................................................................................... 137
Chapter 9
Routing..............................................................................................................................................138
9.1 Overview ...................................................................................................................................... 138
9.2 The Routing Screen ...................................................................................................................... 138
9.2.1 Add/Edit Static Route ......................................................................................................... 139
9.3 The DNS Route Screen ................................................................................................................. 140
9.3.1 The DNS Route Add Screen ............................................................................................... 141
9.4 The Policy Route Screen .............................................................................................................. 141
9.4.1 Add/Edit Policy Route ........................................................................................................ 143
9.5 RIP ............................................................................................................................................... 143
9.5.1 The RIP Screen ..................................................................................................................... 144
Chapter 10
Quality of Service (QoS)..................................................................................................................145
10.1 Overview .................................................................................................................................... 145
10.1.1 What You Can Do in this Chapter ................................................................................... 145
10.2 What You Need to Know ........................................................................................................... 146
10.3 The Quality of Service General Screen ................................................................................... 147
10.4 The Queue Setup Screen ........................................................................................................... 148
10.4.1 Editing a QoS Queue ....................................................................................................... 150
10.5 The Classification Setup Screen ................................................................................................ 151
10.5.1 Add/Edit QoS Class .......................................................................................................... 152
10.6 The QoS Shaper Setup Screen .................................................................................................. 155
10.6.1 Add/Edit a QoS Shaper ................................................................................................... 156
10.7 The QoS Policer Setup Screen ................................................................................................... 156
10.7.1 Add/Edit a QoS Policer ................................................................................................... 157
10.8 Technical Reference .................................................................................................................. 158
Chapter 11
Network Address Translation (NAT)................................................................................................163
11.1 Overview ..................................................................................................................................... 163
11.1.1 What You Can Do in this Chapter ................................................................................... 163
11.1.2 What You Need To Know ................................................................................................. 163
11.2 The Port Forwarding Screen ..................................................................................................... 164
11.2.1 Add/Edit Port Forwarding ................................................................................................ 166
11.3 The Applications Screen ............................................................................................................ 167
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11.3.1 Add New Application ....................................................................................................... 168
11.4 The Port Triggering Screen ......................................................................................................... 168
11.4.1 Add/Edit Port Triggering Rule ..........................................................................................170
11.5 The DMZ Screen .......................................................................................................................... 171
11.6 The ALG Screen .......................................................................................................................... 172
11.7 The Address Mapping Screen ................................................................................................... 172
11.7.1 Add/Edit Address Mapping Rule ..................................................................................... 173
11.8 The Sessions Screen .................................................................................................................... 174
11.9 Technical Reference .................................................................................................................. 175
11.9.1 NAT Definitions ................................................................................................................... 175
11.9.2 What NAT Does ................................................................................................................. 176
11.9.3 How NAT Works .................................................................................................................. 176
11.9.4 NAT Application ................................................................................................................ 176
Chapter 12
Dynamic DNS Setup.........................................................................................................................179
12.1 Overview ..................................................................................................................................... 179
12.1.1 What You Can Do in this Chapter ................................................................................... 179
12.1.2 What You Need To Know ................................................................................................. 179
12.2 The DNS Entry Screen ................................................................................................................. 180
12.2.1 Add/Edit DNS Entry ........................................................................................................... 180
12.3 The Dynamic DNS Screen .......................................................................................................... 181
Chapter 13
Interface Grouping..........................................................................................................................183
13.1 Overview ..................................................................................................................................... 183
13.1.1 What You Can Do in this Chapter ................................................................................... 183
13.2 The Interface Group Screen ...................................................................................................... 183
13.2.1 Interface Group Configuration ....................................................................................... 184
13.2.2 Interface Grouping Criteria ............................................................................................186
Chapter 14
USB Service................. ... ................... .... ... .... ..................................... ... .... .... .....................................188
14.1 Overview ..................................................................................................................................... 188
14.1.1 What You Can Do in this Chapter ................................................................................... 188
14.1.2 What You Need To Know ................................................................................................. 188
14.1.3 Before You Begin ............................................................................................................... 189
14.2 The File Sharing Screen .............................................................................................................. 189
14.2.1 The Add New Share Screen ............................................................................................. 191
14.2.2 The Add New User Screen ............................................................................................... 192
14.3 The Media Server Screen ........................................................................................................... 192
Chapter 15
Firewall..............................................................................................................................................193
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15.1 Overview ..................................................................................................................................... 193
15.1.1 What You Can Do in this Chapter ................................................................................... 193
15.1.2 What You Need to Know ................................................................................................. 194
15.2 The Firewall Screen ..................................................................................................................... 194
15.3 The Protocol Screen .................................................................................................................. 195
15.3.1 Add/Edit a Service ........................................................................................................... 196
15.4 The Access Control Screen ....................................................................................................... 197
15.4.1 Add/Edit an ACL Rule ..................................................................................................... 197
15.5 The DoS Screen ........................................................................................................................... 199
Chapter 16
MAC Filter .........................................................................................................................................200
16.1 Overview .................................................................................................................................... 200
16.2 The MAC Filter Screen ................................................................................................................ 200
Chapter 17
Parental Control ...............................................................................................................................202
17.1 Overview ..................................................................................................................................... 202
17.2 The Parental Control Screen ..................................................................................................... 202
17.2.1 Add/Edit a Parental Control Profile ................................................................................ 203
Chapter 18
Scheduler Rule .................................................................................................................................207
18.1 Overview ..................................................................................................................................... 207
18.2 The Scheduler Rule Screen ........................................................................................................ 207
18.2.1 Add/Edit a Schedule ........................................................................................................ 207
Chapter 19
Certificates .......................................................................................................................................209
19.1 Overview ..................................................................................................................................... 209
19.1.1 What You Can Do in this Chapter ................................................................................... 209
19.2 What You Need to Know ........................................................................................................... 209
19.3 The Local Certificates Screen ................................................................................................... 209
19.3.1 Create Certificate Request ............................................................................................ 210
19.3.2 Load Signed Certificate .................................................................................................. 212
19.4 The Trusted CA Screen ............................................................................................................... 213
19.4.1 View Trusted CA Certificate ............................................................................................ 214
19.4.2 Import Trusted CA Certificate .......................................................................................... 215
Chapter 20
Log ....................................................................................................................................................216
20.1 Overview ..................................................................................................................................... 216
20.1.1 What You Can Do in this Chapter ................................................................................... 216
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20.1.2 What You Need To Know ................................................................................................. 216
20.2 The System Log Screen .............................................................................................................. 217
20.3 The Security Log Screen ............................................................................................................. 217
Chapter 21
Traffic Status .....................................................................................................................................219
21.1 Overview ..................................................................................................................................... 219
21.1.1 What You Can Do in this Chapter ................................................................................... 219
21.2 The WAN Status Screen .............................................................................................................. 219
21.3 The LAN Status Screen ............................................................................................................... 220
21.4 The NAT Status Screen ................................................................................................................ 221
Chapter 22
ARP Table..........................................................................................................................................222
22.1 Overview ..................................................................................................................................... 222
22.1.1 How ARP Works .................................................................................................................. 222
22.2 ARP Table Screen ....................................................................................................................... 223
Chapter 23
Routing Table....................................................................................................................................224
23.1 Overview ..................................................................................................................................... 224
23.2 The Routing Table Screen .......................................................................................................... 224
Chapter 24
xDSL Statistics ............................... .... .... ... ....................................................... .... .... .... ......................226
24.1 The xDSL Statistics Screen .......................................................................................................... 226
Chapter 25
Cellular Statistics .............................................................................................................................228
25.1 Overview ..................................................................................................................................... 228
25.2 The Cellular Statistics Screen ..................................................................................................... 228
Chapter 26
System...............................................................................................................................................230
26.1 Overview ..................................................................................................................................... 230
26.2 The System Screen ...................................................................................................................... 230
Chapter 27
User Account... ... .... .... ....................................................... .... ... .... ....................................................231
27.1 Overview .................................................................................................................................... 231
27.2 The User Account Screen .......................................................................................................... 231
27.2.1 The User Account Add and Edit Screens ....................................................................... 232
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Chapter 28
Remote Management.....................................................................................................................234
28.1 Overview ..................................................................................................................................... 234
28.2 The Remote MGMT Screen ........................................................................................................ 234
28.3 The Trust Domain Screen ............................................................................................................ 235
28.3.1 The Add Trust Domain Screen ......................................................................................... 235
Chapter 29
SNMP .................................................................................................................................................237
29.1 Overview ..................................................................................................................................... 237
29.2 The SNMP Screen ........................................................................................................................ 237
Chapter 30
Time Settings.....................................................................................................................................239
30.1 Overview ..................................................................................................................................... 239
30.2 The Time Screen ......................................................................................................................... 239
Chapter 31
E-mail Notification ...........................................................................................................................241
31.1 Overview .................................................................................................................................. 241
31.2 The E-mail Notification Screen .................................................................................................. 241
31.2.1 E-mail Notification Edit .................................................................................................... 241
Chapter 32
Logs Setting ......................................................................................................................................243
32.1 Overview .................................................................................................................................... 243
32.2 The Logs Setting Screen ............................................................................................................. 243
32.2.1 Example E-mail Log ........................................................................................................... 244
Chapter 33
Firmware Upgrade..... ... ...................................................................................................................246
33.1 Overview ..................................................................................................................................... 246
33.2 The Firmware Screen .................................................................................................................. 246
Chapter 34
Backup/Restore ...............................................................................................................................248
34.1 Overview ..................................................................................................................................... 248
34.2 The Backup/Restore Screen ...................................................................................................... 248
34.3 The Reboot Screen ..................................................................................................................... 250
Chapter 35
Diagnostic.........................................................................................................................................251
35.1 Overview ..................................................................................................................................... 251
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35.1.1 What You Can Do in this Chapter ................................................................................... 251
35.2 What You Need to Know ........................................................................................................... 251
35.3 Ping & TraceRoute & Nslookup ................................................................................................. 252
Chapter 36
Troubleshooting................................................................................................................................253
36.1 Power, Hardware Connections, and LEDs ............................................................................... 253
36.2 VMG Access and Login ............................................................................................................. 254
36.3 Internet Access ........................................................................................................................... 255
36.4 Wireless Internet Access ............................................................................................................. 257
36.5 USB Device Connection ............................................................................................................ 258
36.6 UPnP ............................................................................................................................................. 258
Part III: Appendices......................................................................................259
Appendix A Customer Support ..................................................................................................... 260
Appendix B Wireless LANs............................................................................................................... 266
Appendix C IPv6.............................................................................................................................. 279
Appendix D Services....................................................................................................................... 287
Appendix E Legal Information ....................................................................................................... 291
Index .................................................................................................................................................299
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PART I
User’s Guide
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CHAPTER 1
Introducing the VMG
1.1 Overview
The VMG is a wireless VDSL router. It has a DSL port as well as a Ethernet WAN port for Internet access.
The VMG supports both Packet Transfer Mode (PTM) and Asynchronous Transfer Mode (ATM). It is
backward compatible with ADSL, ADSL2 and ADSL2+ in case VDSL is not available. The VMG also acts as
an IEEE 802.11 b/g/n access point.
Only use firmware for your VMG’s specific model. Refer to the label on
the bottom of your VMG.
The VMG works over the analog telephone system, POTS (Plain Old Telephone Service). The VMG has
one USB port for sharing files via a USB storage device or connecting a cellular dongle for a WAN
backup connection.
Note: Cellular networks refer to 3G only at the time of writing.
Note: See the product page on Zyxel’s website for the list of compatible cellular USB dongles.
1.2 Ways to Manage the VMG
Use any of the following methods to manage the VMG.
• Web Configurator. This is recommended for everyday management of the VMG using a (supported)
web browser.
1.3 Good Habits for Managing the VMG
Do the following things regularly to make the VMG more secure and to manage the VMG more
effectively.
• Change the password. Use a password that’s not easy to guess and that consists of different types of
characters, such as numbers and letters.
• Write down the password and put it in a safe place.
• Back up the configuration (and make sure you know how to restore it). Restoring an earlier working
configuration may be useful if the device becomes unstable or even crashes. If you forget your
password, you will have to reset the VMG to its factory default settings. If you backed up an earlier
configuration file, you would not have to totally re-configure the VMG. You could simply restore your
last configuration.
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1.4 Applications for the VMG
Here are some example uses for which the VMG is well suited.
1.4.1 Internet Access
Computers can connect to the VMG’s LAN ports (or wirelessly).
You can also configure IP filtering on the VMG for secure Internet access. When the IP filter is on, all
incoming traffic from the Internet to your network is blocked by default unless it is initiated from your
network. This means that probes from the outside to your network are not allowed, but you can safely
browse the Internet and download files.
1.4.1.1 DSL
Your VMG provides shared Internet access by connecting the DSL port to the DSL or MODEM jack on a
splitter or your telephone jack. You can have multiple WAN services over one ADSL or VDSL. The VMG
cannot work in ADSL and VDSL mode at the same time.
Note: The ADSL and VDSL lines share the same WAN (layer-2) interfaces that you configure in
the VMG. Refer to Section 6.2 on page 74 for the Network Setting > Broadband screen.
Figure 1 VMG’s Internet Access Application: DSL
DSL
DSL
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1.4.1.2 Ethernet WAN
If you prefer not to use a DSL line and you have another broadband modem or router (such as ADSL)
available, you can connect the Ethernet WAN port to the broadband modem or router. This way, you
can access the Internet via an Ethernet connection and still use the QoS, Firewall and parental control
functions on the VMG.
Figure 2 VMG’s Internet Access Application: Ethernet WAN
1.4.2 VMG’s USB Support
The USB port of the VMG is used for cellular WAN backup, file-sharing and media server.
Cellular WAN (3G) Backup
Connect a supported cellular USB dongle with an active SIM card to the USB port. This adds a second
WAN interface and allows the VMG to wirelessly access the Internet via a cellularnetwork. The cellular
WAN connection is the failover or a backup in case the DSL or Ethernet WAN connection fails.
To set up a cellular connection, click Network Setting > Broadband > Cellular Backup.
To update the supported cellular USB dongle list, download the latest WWAN package from the Zyxel
website and upload it to the VMG using the Maintenance > Firmware Upgrade screen.
Figure 3 VMG’s Internet Access Application: Cellular WAN
DSL
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File Sharing
Use the built-in USB 2.0 port to share files on a USB memory stick or a USB hard drive (B). Use FTP to access
the files on the USB device.
Figure 4 USB File Sharing Application
Media Server
You can also use the VMG as a media server. This lets anyone on your network play video, music, and
photos from a USB device (B) connected to the VMG’s USB port (without having to copy them to
another computer).
Figure 5 USB Media Server Application
DSL
DSL
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1.5 Wireless Access
The VMG is a wireless Access Point (AP) for wireless clients, such as notebook computers or PDAs and
iPads. It allows them to connect to the Internet without having to rely on inconvenient Ethernet cables.
You can configure your wireless network in either the built-in Web Configurator, or using the WPS button.
See Section 1.6.4 on page 23 for more information about how to set up a wireless network with WLAN
and WPS buttons.
Figure 6 Wireless Access Example
1.6 Hardware
1.6.1 Front Panel
The following graphic displays the front panel of the VMG.
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Figure 7 VMG3312-T20A Front Panel
1.6.2 LEDs (Lights)
The following graphic displays the labels of the LEDs.
Figure 8 LEDs on the VMG
None of the LEDs are on if the VMG is not receiving power.
Table 1 LED Descriptions
LED COLOR STATUS DESCRIPTION
POWER
Green On The VMG is receiving power and ready for use.
Blinking The VMG is self-testing.
Red On The VMG detected an error while self-testing, or there is a device
malfunction.
Off The VMG is not receiving power.
ETHERNET1~4
Green On The VMG has a successful 10/100 Mbps Ethernet connection with a device
on the Local Area Network (LAN).
Blinking The VMG is sending or receiving data to/from the LAN at 10/100 Mbps.
Off The VMG does not have an Ethernet connection with the LAN.
WLAN
Green On The wireless network is activated.
Blinking The VMG is communicating with wireless clients.
WPS
Orange Blinking The VMG is setting up a WPS connection with a wireless client.
Off The wireless network is not activated.
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1.6.3 Side Panels
The following graphics display the side panels of the VMG.
DSL
Green On The VDSL line is up.
Blinking The VMG is initializing the VDSL line.
Off The DSL line is down.
Orange On The ADSL line is up.
Slow
Blinking
The VMG is detecting carrier signals.
Fast
Blinking
The VMG is initializing the VDSL line.
WAN
Green On The VMG has a successful 10/100/1000 Mbps Ethernet connection on the
WAN.
Blinking The VMG is sending or receiving data to/from the WAN at 10/100/1000
Mbps.
Off The VMG does not have an Ethernet connection with the WAN.
INTERNET
Green On The VMG has an IP connection but no traffic.
Your device has a WAN IP address (either static or assigned by a DHCP
server). PPP negotiation was successfully completed (if used) and the DSL
connection is up.
Blinking The VMG is sending or receiving IP traffic.
Off There is no Internet connection or the gateway is in bridged mode.
Red On The VMG attempted to make an IP connection but failed. Possible causes
are no response from a DHCP server, no PPPoE response, PPPoE
authentication failed.
USB
Green On The VMG recognizes a USB connection through the USB slot.
Blinking The VMG is sending/receiving data to/from the USB device connected to it.
Off The VMG does not detect a USB connection through the USB slot.
Table 1 LED Descriptions (continued)
LED COLOR STATUS DESCRIPTION
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Figure 9 VMG3312-T20A Side Panel
Figure 10 VMG3312-T20A Side Panel
The following table describes the items on the side panels..
Table 2 Side Panel Buttons
LABEL DESCRIPTION
WLAN Press the WLAN button for more than two seconds to enable the wireless
function.
WPS Press the WPS button for more than five seconds to quickly set up a secure
wireless connection between the device and a WPS-compatible client.
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1.6.4 Using the WLAN and WPS Buttons
If the wireless network is turned off, press the WLAN button for more than two seconds. Once the WLAN
LED turns green, the wireless network is active.
You can also use the WPS button to quickly set up a secure wireless connection between the VMG and
a WPS-compatible client by adding one device at a time.
To activate WPS:
1Make sure the POWER LED is on and not blinking.
2Press the WPS button for more than five seconds and release it.
3Press the WPS button on another WPS-enabled device within range of the VMG. The WPS LED flashes
orange while the VMG sets up a WPS connection with the other wireless device.
4Once the connection is successfully made, the WPS LED shines orange.
To turn off the wireless network, press the WLAN button for more than two seconds. The WLAN LED turns
off when the wireless network is off.
1.6.5 Rear Panel
The following graphic displays the rear panel of the VMG.
Figure 11 VMG3312-T20A Rear Panel
Power
Button
Press the power button after the power cable is connected to start the
device.
USB The USB port is used for cellular WAN backup, file-sharing and media server.
Table 2 Side Panel Buttons (continued)
LABEL DESCRIPTION
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The following table describes the items on the rear panel..
1.6.6 The RESET Button
If you forget your password or cannot access the Web Configurator, you will need to use the RESET
button at the back of the device to reload the factory-default configuration file. This means that you will
lose all configurations that you had previously. The password will be reset to “1234”, and the LAN IP
address will be”192.168.1.1”.
1Make sure the POWER LED is on (not blinking).
2To set the device back to the factory default settings, press the RESET button for five seconds or until the
POWER LED begins to blink and then release it. When the POWER LED begins to blink, the defaults have
been restored and the device restarts.
1.6.7 Wall Mounting
You may need screw anchors if mounting on a concrete or brick wall.
3Select a position free of obstructions on a wall strong enough to hold the weight of the device.
4Mark two holes on the wall at the appropriate distance apart for the screws.
Be careful to avoid damaging pipes or cables located inside the wall
when drilling holes for the screws.
5If using screw anchors, drill two holes for the screw anchors into the wall. Push the anchors into the full
depth of the holes, then insert the screws into the anchors. Do not insert the screws all the way in - leave
a small gap of about 0.5 cm.
If not using screw anchors, use a screwdriver to insert the screws into the wall. Do not insert the screws all
the way in - leave a gap of about 0.5 cm.
6Make sure the screws are fastened well enough to hold the weight of the VMG with the connection
cables.
7Align the holes on the back of the VMG with the screws on the wall. Hang the VMG on the screws.
Table 3 Rear Panel Ports
LABEL DESCRIPTION
Power Connect the power cable and press the power button to start the device.
Reset Press the button to return theVMG to the factory defaults.
LAN1 ~ LAN4 Connect computers or other Ethernet devices to Ethernet ports for Internet
access.
WAN Connect an Ethernet cable to the Ethernet WAN port for Internet access.
DSL Connect a RJ-11 cable to the DSL port for Internet access.
Table 4 Wall Mounting Information
Distance between holes 126 mm
M4 Screws Two
Screw anchors (optional) Two
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Figure 12 Wall Mounting Example
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CHAPTER 2
The Web Configurator
2.1 Overview
The web configurator is an HTML-based management interface that allows easy VMG setup and
management via Internet browser. Use Internet Explorer 8.0 and later versions or Mozilla Firefox 3 and
later versions or Safari 2.0 and later versions. The recommended screen resolution is 1024 by 768 pixels.
In order to use the web configurator you need to allow:
• Web browser pop-up windows from your VMG. Web pop-up blocking is enabled by default in
Windows XP SP (Service Pack) 2.
• JavaScript (enabled by default).
• Java permissions (enabled by default).
2.1.1 Accessing the Web Configurator
1Make sure your VMG hardware is properly connected (refer to the Quick Start Guide).
2Launch your web browser. If the VMG does not automatically re-direct you to the login screen, go to
http://192.168.1.1.
3A password screen displays. To access the administrative web configurator and manage the VMG, type
the default username admin and password 1234 in the password screen and click Login. If you have
changed the password, enter your password and click Login.
Figure 13 Password Screen
4The following screen displays if you have not yet changed your password. Enter a new password, retype
it to confirm and click Apply.
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Figure 14 Change Password Screen
5The Quick Start Wizard screen appears. You can configure basic Internet access, and wireless settings.
See Chapter 3 on page 33 for more information.
6After you finished or closed the Quick Start Wizard screen, the Network Map page appears.
Figure 15 Network Map
7Click the right arrow icon to display the Status screen, where you can view the VMG’s interface and
system information.
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2.2 Web Configurator Layout
Figure 16 Screen Layout
As illustrated above, the main screen is divided into these parts:
•A - title bar
•B - main window
•C - navigation panel
2.2.1 Title Bar
The title bar provides some icons in the upper right corner.
The icons provide the following functions.
2.2.2 Main Window
The main window displays information and configuration fields. It is discussed in the rest of this
document.
A
B
C
Table 5 Web Configurator Icons in the Title Bar
ICON DESCRIPTION
Language: Select the language you prefer.
Quick Start: Click this icon to open screens where you can configure the VMG’s time zone
Internet access, and wireless settings.
Logout: Click this icon to log out of the web configurator.
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After you click the right arrow icon on the Connection Status (Network Map) page, the Status screen is
displayed. See Chapter 5 on page 67 for more information about the Status screen.
2.2.3 Navigation Panel
Use the menu items on the navigation panel to open screens to configure VMG features. The following
tables describe each menu item.
Table 6 Navigation Panel Summary
LINK TAB FUNCTION
Connection Status This screen shows the network status of the VMG and computers/devices
connected to it.
Network Setting
Broadband Broadband Use this screen to view and configure ISP parameters, WAN IP address
assignment, and other advanced properties. You can also add new
WAN connections.
Cellular Backup Use this screen to configure cellular WAN connection.
Advanced Use this screen to enable or disable PTM over ADSL, Annex M/Annex J,
and DSL PhyR functions.
Wireless General Use this screen to configure the wireless LAN settings and WLAN
authentication/security settings.
Guest/More AP Use this screen to configure multiple BSSs on the VMG.
MAC
Authentication
Use this screen to block or allow wireless traffic from wireless devices of
certain SSIDs and MAC addresses to the VMG.
WPS Use this screen to configure and view your WPS (Wi-Fi Protected Setup)
settings.
WMM Use this screen to enable or disable Wi-Fi MultiMedia (WMM).
Others Use this screen to configure advanced wireless settings.
Channel Status Use this screen to scan wireless LAN channel noises and view the results.
Home
Networking LAN Setup Use this screen to configure LAN TCP/IP settings, and other advanced
properties.
Static DHCP Use this screen to assign specific IP addresses to individual MAC
addresses.
UPnP Use this screen to turn UPnP and UPnP NAT-T on or off.
Additional
Subnet
Use this screen to configure IP alias and public static IP.
STB Vendor ID Use this screen to configure the Vendor IDs of the connected Set Top Box
(STB) devices, which have the VMG automatically create static DHCP
entries for the STB devices when they request IP addresses.
Wake on LAN Use this screen to remotely turn on a device on the local network.
TFTP Server Name Configure a TFTP server name which is sent to clients using DHCP option
66.
Routing Static Route Use this screen to view and set up static routes on the VMG.
DNS Route Use this screen to forward DNS queries for certain domain names through
a specific WAN interface to its DNS server(s).
Policy Route Use this screen to configure policy routing on the VMG.
RIP Use this screen to configure Routing Information Protocol to exchange
routing information with other routers.
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QoS General Use this screen to enable QoS and traffic prioritizing. You can also
configure the QoS rules and actions.
Queue Setup Use this screen to configure QoS queues.
Classification
Setup
Use this screen to define a classifier.
Shaper Setup Use this screen to limit outgoing traffic rate on the selected interface.
Policer Setup
NAT Port Forwarding Use this screen to make your local servers visible to the outside world.
Applications Use this screen to configure servers behind the VMG.
Port Triggering Use this screen to change your VMG’s port triggering settings.
DMZ Use this screen to configure a default server which receives packets from
ports that are not specified in the Port Forwarding screen.
ALG Use this screen to enable or disable SIP ALG.
Address Mapping Use this screen to change your VMG’s address mapping settings.
Sessions Use this screen to configure the maximum number of NAT sessions each
client host is allowed to have through the VMG.
DNS DNS Entry Use this screen to view and configure DNS routes.
Dynamic DNS Use this screen to allow a static hostname alias for a dynamic IP address.
Interface
Grouping Interface
Grouping
Use this screen to map a port to a PVC or bridge group.
USB Service File Sharing Use this screen to enable file sharing via the VMG.
Media Server Use this screen to use the VMG as a media server.
Security
Firewall General Use this screen to configure the security level of your firewall.
Protocol Use this screen to add Internet services and configure firewall rules.
Access Control Use this screen to enable specific traffic directions for network services.
DoS Use this screen to activate protection against Denial of Service (DoS)
attacks.
MAC Filter MAC Filter Use this screen to block or allow traffic from devices of certain MAC
addresses to the VMG.
Parental
Control Parental Control Use this screen to block web sites with the specific URL.
Scheduler Rule Scheduler Rule Use this screen to configure the days and times when a configured
restriction (such as parental control) is enforced.
Certificates Local Certificates Use this screen to view a summary list of certificates and manage
certificates and certification requests.
Trusted CA Use this screen to view and manage the list of the trusted CAs.
System Monitor
Table 6 Navigation Panel Summary (continued)
LINK TAB FUNCTION
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Log System Log Use this screen to view the status of events that occurred to the VMG.
You can export or e-mail the logs.
Security Log Use this screen to view all security related events. You can select level
and category of the security events in their proper drop-down list
window.
Levels include:
•Emergency
•Alert
• Critical
• Error
• Warning
•Notice
• Informational
•Debugging
Categories include:
• Account
• Attack
•Firewall
• MAC Filter
Traffic Status WAN Use this screen to view the status of all network traffic going through the
WAN port of the VMG.
LAN Use this screen to view the status of all network traffic going through the
LAN ports of the VMG.
NAT Use this screen to view NAT statistics for connected hosts.
ARP table ARP table Use this screen to view the ARP table. It displays the IP and MAC address
of each DHCP connection.
Routing Table Routing Table Use this screen to view the routing table on the VMG.
xDSL Statistics xDSL Statistics Use this screen to view the VMG’s xDSL traffic statistics.
Cellular
Statistics Cellular Statistics Use this screen to look at cellular Internet connection status.
Maintenance
System System Use this screen to set Device name and Domain name.
User Account User Account Use this screen to change user password on the VMG.
Remote
Management MGMT Services Use this screen to enable specific traffic directions for network services.
Trust Domain Use this screen to configure a list of public IP addresses which are
allowed to access the VMG.
SNMP SNMP Use this screen to configure SNMP (Simple Network Management
Protocol) settings.
Time Time Use this screen to change your VMG’s time and date.
Email
Notification Email Notification Use this screen to configure up to two mail servers and sender addresses
on the VMG.
Log Setting Log Setting Use this screen to change your VMG’s log settings.
Firmware
Upgrade Firmware
Upgrade
Use this screen to upload firmware to your VMG.
Backup Restore Backup/Restore Use this screen to backup and restore your VMG’s configuration
(settings) or reset the factory default settings.
Table 6 Navigation Panel Summary (continued)
LINK TAB FUNCTION
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Reboot Reboot Use this screen to reboot the VMG without turning the power off.
Diagnostic Ping&Traceroute
&Nslookup
Use this screen to identify problems with the DSL connection. You can
use Ping, TraceRoute, or Nslookup to help you identify problems.
Table 6 Navigation Panel Summary (continued)
LINK TAB FUNCTION
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CHAPTER 3
Quick Start
3.1 Overview
Use the Quick Start screens to configure the VMG’s time zone, basic Internet access, and wireless
settings.
Note: See the technical reference chapters (starting on Chapter 4 on page 36) for
background information on the features in this chapter.
3.2 Quick Start Setup
1The Quick Start Wizard appears automatically after login. Or you can click the Quick Start icon in the top
right corner of the web configurator to open the quick start screens. Select the time zone of your
location. Click Next.
Figure 17 Quick Start - Welcome
2Enter your Internet connection information in this screen. The screen and fields to enter may vary
depending on your current connection type. Click Next.
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Figure 18 Quick Start - Internet Connection
3Turn the wireless LAN on or off. If you keep it on, record the security settings so you can configure your
wireless clients to connect to the VMG. Click Save.
Figure 19 Quick Start - Wireless Setting
4Your VMG saves your settings and attempts to connect to the Internet. Click Close to complete the
setup.
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Figure 20 Quick Start - Result Summary
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CHAPTER 4
Tutorials
4.1 Overview
This chapter shows you how to use the VMG’s various features.
•Setting Up an ADSL PPPoE Connection, see page 36
•Setting Up a Secure Wireless Network, see page 39
•Setting Up Multiple Wireless Groups, see page 44
•Using the File Sharing Feature, see page 48
•Using the Media Server Feature, see page 51
•Configuring Static Route for Routing to Another Network, see page 55
•Configuring QoS Queue and Class Setup, see page 58
•Access the VMG Using DDNS, see page 61
•Configuring the MAC Address Filter, see page 62
•Access Your Shared Files From a Computer, see page 63
4.2 Setting Up an ADSL PPPoE Connection
This tutorial shows you how to set up an ADSL Internet connection using the Web Configurator.
If you connect to the Internet through an ADSL connection, use the information from your Internet
Service Provider (ISP) to configure the VMG. Be sure to contact your service provider for any information
you need to configure the Broadband screens.
1Click Network Setting > Broadband to open the following screen. Click Add New WAN Interface.
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2In this example, the DSL connection has the following information.
3Select Enablein the Active field. Enter the General and ATM PVC Configuration settings as provided
above.
Set the Type to ADSL over ATM.
Choose the Encapsulation specified by your DSL service provider. For this example, the service provider
requires a username and password to establish Internet connection. Therefore, select PPPoE as the WAN
encapsulation type.
Set the IPv6/IPv4 Mode to IPv4 Only.
4Enter the account information provided to you by your DSL service provider.
5Configure this rule as your default Internet connection by selecting the Apply a s Default Gateway check
box. Then select DNS as Static and enter the DNS server addresses provided to you, such as 192.168.5.2
(DNS server1)/192.168.5.1 (DNS server2).
6Leave the rest of the fields to the default settings.
7Click Apply to save your settings.
General
Name MyDSLConnection
Type ADSL over ATM
Connection Mode Routing
Encapsulation PPPoE
IPv6/IPv4 Mode IPv4
ATM PVC Configuration
VPI/VCI 36/48
Encapsulation Mode LLC/SNAP-Bridging
Service Category UBR without PCR
Account Information
PPP User Name 1234@DSL-Ex.com
PPP Password ABCDEF!
PPPoE Service Name MyDSL
Static IP Address 192.168.1.32
Others Authentication Method: AUTO
PPPoE Passthrough: Disabled
NAT: Enabled
IGMP Multicast Proxy: Enabled
Apply as Default Gateway: Enabled
VLAN: Disabled
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8You should see a summary of your new DSL connection setup in the Broadband screen as follows.
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Try to connect to a website to see if you have correctly set up your Internet connection. Be sure to
contact your service provider for any information you need to configure the WAN screens.
4.3 Setting Up a Secure Wireless Network
Thomas wants to set up a wireless network so that he can use his notebook to access the Internet. In this
wireless network, the VMG serves as an access point (AP), and the notebook is the wireless client. The
wireless client can access the Internet through the AP.
Thomas has to configure the wireless network settings on the VMG. Then he can set up a wireless
network using WPS (Section 4.3.2 on page 41) or manual configuration (Section 4.3.3 on page 44).
4.3.1 Configuring the Wireless Network Settings
This example uses the following parameters to set up a wireless network.
1Click Network Setting > Wireless to open the General screen. Select More Secure as the security level
and WPA2-PSK as the security mode. Configure the screen using the provided parameters (see
page 39). Click Apply.
DSL
SSID Example
Security Mode WPA2-PSK
Pre-Shared Key DoNotStealMyWirelessNetwork
802.11 Mode 802.11b/g/n Mixed
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2Go to the Wireless > Others screen and select 802.11b/g/n Mixed in the 802.11 Mode field. Click Apply.
Thomas can now use the WPS feature to establish a wireless connection between his notebook and the
VMG (see Section 4.3.2 on page 41). He can also use the notebook’s wireless client to search for the
VMG (see Section 4.3.3 on page 44).
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4.3.2 Using WPS
This section shows you how to set up a wireless network using WPS. It uses the VMG as the AP and Zyxel
NWD210N as the wireless client which connects to the notebook.
Note: The wireless client must be a WPS-aware device (for example, a WPS USB adapter or
PCMCIA card).
There are two WPS methods to set up the wireless client settings:
•Push Button Configuration (PBC) - simply press a button. This is the easier of the two methods.
•PIN Configuration - configure a Personal Identification Number (PIN) on the VMG. A wireless client
must also use the same PIN in order to download the wireless network settings from the VMG.
Push Button Configuration (PBC)
1Make sure that your VMG is turned on and your notebook is within the cover range of the wireless signal.
2Make sure that you have installed the wireless client driver and utility in your notebook.
3In the wireless client utility, go to the WPS setting page. Enable WPS and press the WPS button (Start or
WPS button).
4Push and hold the WPS button located on the VMG’s front panel for more than 5 seconds. Alternatively,
you may log into VMG’s web configurator and go to the Network Setting > Wireless > WPS screen.
Enable the WPS function for method 1 and click Apply. Then click the WPS button.
Note: Your VMG has a WPS button located on the side of the device as well as a WPS button
in its configuration utility. Both buttons have exactly the same function: you can use one
or the other.
Note: It doesn’t matter which button is pressed first. You must press the second button within
two minutes of pressing the first one.
1
2
3
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The VMG sends the proper configuration settings to the wireless client. This may take up to two minutes.
The wireless client is then able to communicate with the VMG securely.
The following figure shows you an example of how to set up a wireless network and its security by
pressing a button on both VMG and wireless client.
Example WPS Process: PBC Method
PIN Configuration
When you use the PIN configuration method, you need to use both the VMG’s web configurator and
the wireless client’s utility.
1Launch your wireless client’s configuration utility. Go to the WPS settings and select the PIN method to
get a PIN number.
2Log into VMG’s web configurator and go to the Network Setting > Wireless > WPS screen. Enable the
WPS function and click Apply.
DSL
DSL
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3Enter the PIN number of the wireless client and click the Register button. Activate WPS function on the
wireless client utility screen within two minutes.
The VMG authenticates the wireless client and sends the proper configuration settings to the wireless
client. This may take up to two minutes. The wireless client is then able to communicate with the VMG
securely.
The following figure shows you how to set up a wireless network and its security on a VMG and a wireless
client by using PIN method.
1
2
3
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Example WPS Process: PIN Method
4.3.3 Without WPS
Use the wireless adapter’s utility installed on the notebook to search for the “Example” SSID. Then enter
the “DoNotStealMyWirelessNetwork” pre-shared key to establish an wireless Internet connection.
Note: The VMG supports IEEE 802.11b and IEEE 802.11g wireless clients. Make sure that your
notebook or computer’s wireless adapter supports one of these standards.
4.4 Setting Up Multiple Wireless Groups
Company A wants to create different wireless network groups for different types of users as shown in the
following figure. Each group has its own SSID and security mode.
DSL
DSL
DSL
DSL
DSL
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• Employees in Company A will use a general Company wireless network group.
• Higher management level and important visitors will use the VIP group.
• Visiting guests will use the Guest group, which has a different SSID and password.
Company A will use the following parameters to set up the wireless network groups.
1Click Network Setting > Wireless to open the General screen. Use this screen to set up the company’s
general wireless network group. Configure the screen using the provided parameters and click Apply.
COMPANY VIP GUEST
SSID Company VIP Guest
Security Level More Secure More Secure More Secure
Security Mode WPA2-PSK WPA2-PSK WPA2-PSK
Pre-Shared Key ForCompanyOnly 123456789 guest123
DSL
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2Click Network Setting > Wireless > Guest/More AP to open the following screen. Click the Edit icon to
configure the second wireless network group.
3Configure the screen using the provided parameters and click Apply.
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4In the Guest/More AP screen, click the Edit icon to configure the third wireless network group.Configure
the screen using the provided parameters and click Apply.
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5Check the status of VIP and Guest in the Guest/More AP screen. The yellow bulbs signify that the SSIDs
are active and ready for wireless access.
4.5 Using the File Sharing Feature
In this section you can:
• Set up file sharing of your USB device from the VMG.
• Access the shared files of your USB device from a computer.
4.5.1 Set Up File Sharing
To set up file sharing you need to connect your USB device, enable file sharing and set up your share(s).
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Before enabling file sharing in the VMG, please set up your shares beforehand in the USB. Also, the
following special characters are not allowed for the USB share name: ", ', `, <, >, ^, $, |, &, ;, \, /, :, *, and
?.
4.5.1.1 Activate File Sharing
Connect your USB device to the USB port at the side panel of the VMG.
Click Network Setting > USB Service > File Sharing. Select Enable and click Apply to activate the file
sharing function. The VMG automatically adds your USB device to the Information.
4.5.1.2 Set up File Sharing on Your VMG
You also need to set up file sharing on your VMG in order to share files.
1Click Add New Share in the File Sharing screen to add a new share. Select your USB device from the
Volume drop-down list box.
2Click Browse to browse through all the files on your USB device. Select the folder that you want to add as
a share. In this example, select BobShare. Click Apply.
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If the share names include the following special characters: ", ', `, <, >, ^, $, |, &, ;, \, /, :, *, and ?, the
following screen will appear. To avoid this, please correct your share names in the USB, and repeat the
steps above.
3It’s mandatory for you to add a description for the share. Also, if you want the share to be accessed by
users connecting to the VMG, you can select Public in Access Level or select Security to specific users’
use only. Please note that you need to create the users’ accounts that are eligible to access the secure
shares beforehand under Account Management, if you want to configure the Access Level to Security.
For detailed information, please refer to the steps below. The Add Share Directory screen should look like
the following. Click Apply to finish.
4This sets up the file sharing server. You can see the USB storage device listed in the table below.
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5If you want specific users only to access the shares, you need to Add New Users in Account
Management. Once you click the Add New User button, you’ll be directed to the User Account screen.
To create a user account that can access the secured shares on the USB device, click the Add New
Account button in the Network Setting > Maintenance > User Account screen.
Please see Chapter 29 on page 225, for detailed information about User Account screen.
6After you create a new user account, the screen should look like the following.
4.5.2 Access Your Shared Files From a Computer
You can use Windows Explorer to access the file storage devices connected to the VMG.
Note: The examples in this User’s Guide show you how to use Microsoft’s Windows 7 to browse
your shared files. Refer to your operating system’s documentation for how to browse
your file structure.
Open Windows Explorer to access BobShare using Windows Explorer browser.
In Windows Explorer’s Address bar type a double backslash “\\” followed by the IP address of the VMG
(the default IP address of the VMG is 192.168.1.1) and press [ENTER]. The share folder BobShare is
available.
Once you access BobShare via your VMG, you do not have to relogin unless you restart your computer.
4.6 Using the Media Server Feature
Use the media server feature to play files on a computer or on your television (using DMA-2500).
This section shows you how the media server feature works using the following media clients:
• Microsoft (MS) Windows Media Player
Media Server works with Windows 7. Make sure your computer is able to play media files (music,
videos and pictures).
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• Zyxel DMA-2500, a digital media adapter
You need to set up the DMA-2500 to work with your television (TV). Refer to the DMA-2500 Quick Start
Guide for the correct hardware connections.
Before you begin, connect the USB storage device containing the media files you want to play to the
USB port of your VMG.
4.6.1 Configuring the VMG
To use your VMG as a media server, click Network Setting > USB Service > Media Server.
Enable Media Server, select an interface on which you want to enable the media server function, enter
the path clients use to access the media files on a USB storage device connected to the VMG, and click
Apply. This enables DLNA-compliant media clients to play the video, music and image files in your USB
storage device.
4.6.2 Using Windows Media Player
This section shows you how to play the media files on the USB storage device connected to your VMG
using Windows Media Player.
Windows 7
1Open Windows Media Player. It should automatically detect the VMG.
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If you cannot see the VMG in the left panel as shown above, go to Organize > Manage Libraries >
Music/Videos/Pictures/Recorded TV > Add > \\192.16 8.1.1\BobShare . (Select the folder containing the
media you wish to upload to Windows Media Player.)
2In the right panel, you should see a list of files available in the USB storage device.
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4.6.3 Using a Digital Media Adapter
This section shows you how you can use the VMG with a Zyxel DMA-2500 to play media files stored in the
USB storage device in your TV screen.
Note: For this tutorial, your DMA-2500 should already be set up with the TV according to the
instructions in the DMA-2500 Quick Start Guide.
1Connect the DMA-2500 to an available LAN port in your VMG.
2Turn on the TV and wait for the DMA-2500 Home screen to appear. Using the remote control, go to
MyMedia to open the following screen. Select the GPON Device as your media server.
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3The screen shows you the list of available media files in the USB storage device. Select the file you want
to open and push the Play button in the remote control.
4.7 Configuring Static Route for Routing to Another
Network
In order to extend your Intranet and control traffic flowing directions, you may connect a router to the
VMG’s LAN. The router may be used to separate two department networks. This tutorial shows how to
configure a static routing rule for two network routings.
In the following figure, router R is connected to the VMG’s LAN. R connects to two networks, N1
(192.168.1.x/24) and N2 (192.168.10.x/24). If you want to send traffic from computer A (in N1 network) to
computer B (in N2 network), the traffic is sent to the VMG’s WAN default gateway by default. In this
case, B will never receive the traffic.
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You need to specify a static routing rule on the VMG to specify R as the router in charge of forwarding
traffic to N2. In this case, the VMG routes traffic from A to R and then R routes the traffic to B.
This tutorial uses the following example IP settings:
Table 7 IP Settings in this Tutorial
DEVICE / COMPUTER IP ADDRESS
The VMG’s WAN 172.16.1.1
The VMG’s LAN 192.168.1.1
IP Type IPv4
Use Interface VDSL
A192.168.1.34
DSL
DSL
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To configure a static route to route traffic from N1 to N2:
1Log into the VMG’s Web Configurator in advanced mode.
2Click Network Setting > Routing.
3Click Add new Static Route in the Static Route screen.
4Configure the Static Route Setup screen using the following settings:
4a Select Enable in the Active field. Enter the Route Name as R.
4b Set IP Type to IPv4.
4c Type 192.168.10.0 and subnet mask 255.255.255.0 for the destination, N2.
4d Select Enable in the Use Gateway IP Address field. Type 192.168.1.253 (R’s N1 address) in the
Gateway IP Address field.
4e Select VDSL as the Use Interface.
4f Click OK.
Now B should be able to receive traffic from A. You may need to additionally configure B’s firewall
settings to allow specific traffic to pass through.
R’s N1 192.168.1.253
R’s N2 192.168.10.2
B192.168.10.33
Table 7 IP Settings in this Tutorial
DEVICE / COMPUTER IP ADDRESS
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4.8 Configuring QoS Queue and Class Setup
This section contains tutorials on how you can configure the QoS screen.
Let’s say you are a team leader of a small sales branch office. You want to prioritize e-mail traffic
because your task includes sending urgent updates to clients at least twice every hour. You also upload
data files (such as logs and e-mail archives) to the FTP server throughout the day. Your colleagues use
the Internet for research, as well as chat applications for communicating with other branch offices.
In the following figure, your Internet connection has an upstream transmission bandwidth of 10,000 kbps.
For this example, you want to configure QoS so that e-mail traffic gets the highest priority with at least
5,000 kbps. You can do the following:
• Configure a queue to assign the highest priority queue (1) to e-mail traffic going to the WAN
interface, so that e-mail traffic would not get delayed when there is network congestion.
• Note the IP address (192.168.1.23 for example) and/or MAC address (AA:FF:AA:FF:AA:FF for example)
of your computer and map it to queue 7.
Note: QoS is applied to traffic flowing out of the VMG.
Traffic that does not match this class is assigned a priority queue based on the internal QoS mapping
table on the VMG.
QoS Example
1Click Network Setting > QoS > General and select Enable. Set your WAN Managed Upstream Bandwidth
to 10,000 kbps (or leave this blank to have the VMG automatically determine this figure). Click Apply.
Tutorial: Advanced > QoS
2Click Queue Setup > Edit to modify a queue. Enter or select the following values:
•Name: E-mail
•Interface: WAN
10,000 kbps
DSL
Your computer
IP=192.168.1.23
A colleague’s computer
Other traffic: Automatic classifier
and/or
MAC=AA:FF:AA:FF:AA:FF
Email traffic: Highest priority
DSL
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•Priority: 1 (High)
•Weight: 8
Tutor ial: Advanced > Q oS > Queue Setup
3Click Classification Setup > Add new Classification to create a new class. Select Enable in the Active
field and follow the settings as shown in the screen below.
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Tutorial: Advanced > Q oS > Class Setup
This maps e-mail traffic coming from port 25 to the highest priority, which you have created in the
previous screen (see the IP Protocol field). This also maps your computer’s IP address and MAC address
to the E-mail queue (see the Source fields).
Class Name Give a class name to this traffic, such as E-mail in this example.
From Interface This is the interface from which the traffic will be coming from. Select LAN1 for this example.
Ether Type Select IP to identify the traffic source by its IP address or MAC address.
IP Address Type the IP address of your computer - 192.168.1.23. Type the IP Subnet Mask if you know it.
MAC Address Type the MAC address of your computer - AA:FF:AA:FF:AA:FF. Type the MAC Mask if you know it.
To Queue Index Link this to an item in the Network Setting > QoS > Queue Setup screen, which is the E-mail queue
created in this example.
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4.9 Access the VMG Using DDNS
If you connect your VMG to the Internet and it uses a dynamic WAN IP address, it is inconvenient for you
to manage the device from the Internet. The VMG’s WAN IP address changes dynamically. Dynamic
DNS (DDNS) allows you to access the VMG using a domain name.
To use this feature, you have to apply for DDNS service at, for example, www.dyndns.org.
This tutorial covers:
•Registering a DDNS Account on www.dyndns.org
•Configuring DDNS on Your VMG
•Testing the DDNS Setting
Note: If you have a private WAN IP address, then you cannot use DDNS.
4.9.1 Registering a DDNS Account on www.dyndns.org
1Open a browser and type http://www.dyndns.org.
2Apply for a user account. This tutorial uses UserName1 and 12345 as the username and password.
3Log into www.dyndns.org using your account.
4Add a new DDNS host name. This tutorial uses the following settings as an example.
• Hostname: zyxelrouter.dyndns.org
• Service Type: Host with IP address
• IP Address: Enter the WAN IP address that your VMG is currently using. You can find the IP address on
the VMG’s Web Configurator Status page.
Then you will need to configure the same account and host name on the VMG later.
4.9.2 Configuring DDNS on Yo ur VMG
Configure the following settings in the Network Setting > DNS > Dynamic DNS screen.
•Select Enable Dynamic DNS.
•Select www.DynDNS.com as the service provider.
DSL
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•Type zyxelrouter.dyndns.org in the Host Name field.
• Enter the user name (UserName1) and password (12345).
Click Apply.
4.9.3 Testing the DDNS Setting
Now you should be able to access the VMG from the Internet. To test this:
1Open a web browser on the computer (using the IP address a.b.c.d) that is connected to the Internet.
2Type http://zyxelrouter.dyndns.org and press [Enter].
3The VMG’s login page should appear. You can then log into the VMG and manage it.
4.10 Configuring the MAC Address Filter
Thomas noticed that his daughter Josephine spends too much time surfing the web and downloading
media files. He decided to prevent Josephine from accessing the Internet so that she can concentrate
on preparing for her final exams.
Josephine’s computer connects wirelessly to the Internet through the VMG. Thomas decides to use the
Security > MAC Filter screen to grant wireless network access to his computer but not to Josephine’s
computer.
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1Click Security > MAC Filter to open the MAC Filter screen. Select the Enable check box to activate MAC
filter function.
2Select Allow. Then enter the host name and MAC address of Thomas’ computer in this screen. Click
Apply.
Thomas can also grant access to the computers of other members of his family and friends. However,
Josephine and others not listed in this screen will no longer be able to access the Internet through the
VMG.
4.11 Access Your Shared Files From a Computer
Here is how to use an FTP program to access a file storage device connected to the VMG’s USB port.
Note: This example uses the FileZilla FTP program to browse your shared files.
DSL
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1In FileZilla enter the IP address of the VMG (the default is 192.168.1.1), your account’s user name and
password and port 21 and click Quickconnect. A screen asking for password authentication appears.
File Sharing via Windows Explorer
2Once you log in the USB device displays in the mnt folder.
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PART II
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CHAPTER 5
Network Map and Status
Screens
5.1 Overview
After you log into the Web Configurator, the Network Map screen appears. This shows the network
connection status of the VMG and clients connected to it.
You can use the Status screen to look at the current status of the VMG, system resources, and interfaces
(LAN, WAN, and WLAN).
5.2 The Network Map Screen
Use this screen to view the network connection status of the device and its clients. A warning message
appears if there is a connection problem.
Figure 21 Network Map: Icon View Mode
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If you want to view information about a client, click the client’s name and Info. Click the IP address if
you want to change it. If you want to change the name or icon of the client, click Change icon/name.
If you prefer to view the status in a list, click List View in the Viewing mode selection box. You can
configure how often you want the VMG to update this screen in Refresh interval.
Figure 22 Network Map: List View Mode
5.3 The Status Screen
Use this screen to view the status of the VMG. Click the right arrow icon in the Network Map (Connection
Status) screen to open this screen.
Figure 23 Status Screen
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Each field is described in the following table.
Table 8 Status Screen
LABEL DESCRIPTION
Refresh Interval Select how often you want the VMG to update this screen.
Device Information
Host Name This field displays the VMG system name. It is used for identification.
Model Number This shows the model number of your VMG.
Serial Number This shows the serial number of your VMG.
Firmware
Version This is the current version of the firmware inside the VMG.
WAN Information (These fields display when you have a WAN connection.)
Encapsulation This field displays the current encapsulation method.
IP Address This field displays the current IP address of the VMG in the WAN. Click Release to release your
IP address to 0.0.0.0. If you want to renew your IP address, click Renew.
IP Subnet Mask This field displays the current subnet mask in the WAN.
MAC Address This field displays the WAN Ethernet adapter MAC (Media Access Control) Address of your
VMG.
Primary/
Secondary DNS
Server
This field displays the first/second DNS server IP address assigned to the VMG.
DHCP This field displays whether the WAN interface is using a DHCP IP address or a static IP address.
Choices are:
Client - The WAN interface can obtain an IP address from a DHCP server.
None - The WAN interface is using a static IP address.
LAN Information
IP Address This is the current IP address of the VMG in the LAN.
IP Subnet Mask This is the current subnet mask in the LAN.
IPv6 Link Local
Address This field displays the current link-local address of the VMG for the LAN interface.
DHCP This field displays what DHCP services the VMG is providing to the LAN. The possible values
are:
Server - The VMG is a DHCP server in the LAN. It assigns IP addresses to other computers in
the LAN.
Relay - The VMG acts as a surrogate DHCP server and relays DHCP requests and responses
between the remote server and the clients.
Disable - The VMG is not providing any DHCP services to the LAN.
MAC Address This shows the LAN Ethernet adapter MAC (Media Access Control) Address of your VMG.
WLAN 2.4G Information
MAC Address This shows the wireless adapter MAC (Media Access Control) Address of the wireless
interface.
Status This displays whether the WLAN is activated.
SSID This is the descriptive name used to identify the VMG in a wireless LAN.
Channel This is the channel number used by the wireless interface now.
Security This displays the type of security mode the wireless interface is using in the wireless LAN.
802.11 Mode This displays the type of 802.11 mode the wireless interface is using in the wireless LAN.
WPS This displays whether WPS is activated on the wireless interface.
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Security
Firewall This displays the firewall’s current security level.
System Status
System Up Time This field displays how long the VMG has been running since it last started up. The VMG starts
up when you plug it in, when you restart it (Maintenance > Reboot), or when you reset it.
Current Date/
Time This field displays the current date and time in the VMG. You can change this in
Maintenance> Time Setting.
System Resource
CPU Usage This field displays what percentage of the VMG’s processing ability is currently used. When
this percentage is close to 100%, the VMG is running at full load, and the throughput is not
going to improve anymore. If you want some applications to have more throughput, you
should turn off other applications (for example, using QoS; see Chapter 10 on page 145).
Memory Usage This field displays what percentage of the VMG’s memory is currently used. Usually, this
percentage should not increase much. If memory usage does get close to 100%, the VMG is
probably becoming unstable, and you should restart the device. See Section 34.2 on page
248, or turn off the device (unplug the power) for a few seconds.
NAT Session
Usage This field displays what percentage of the VMG supported NAT sessions are currently being
used. This field also displays the number of active NAT sessions and the maximum number of
NAT sessions the VMG can support.
Interface Status
Interface This column displays each interface the VMG has.
Status This field indicates the interface’s use status.
For the LAN and Ethernet WAN interfaces, this field displays Up when using the interface and
No Link when not using the interface.
For the WLAN interface, this field displays the enabled (Up) or disabled (Disable) state of the
interface.
For the DSL interface, this field displays Down (line down), Up (line up or connected), Drop
(dropping a call) if you're using PPPoE encapsulation, and No Link when not using the
interface.
For the cellular interface, this field displays Up when using the interface and No Device when
no device is detected in any USB slot.
Rate For the LAN and Ethernet WAN interfaces, this displays the port speed and duplex setting.
For the DSL interface, it displays the downstream and upstream transmission rate.
For the WLAN interface, it displays the maximum transmission rate or N/A with WLAN
disabled.
For the cellular interface, this field displays signal strength bars when a cellular device is
installed in a USB slot and N/A when no device is detected in the USB slot.
Table 8 Status Screen (continued)
LABEL DESCRIPTION
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CHAPTER 6
Broadband
6.1 Overview
This chapter discusses the VMG’s Broadband screens. Use these screens to configure your VMG for
Internet access.
A WAN (Wide Area Network) connection is an outside connection to another network or the Internet. It
connects your private networks, such as a LAN (Local Area Network) and other networks, so that a
computer in one location can communicate with computers in other locations.
Figure 24 LAN and WAN
6.1.1 What You Can Do in this Chapter
• Use the Broadband screen to view, remove or add a WAN interface. You can also configure the WAN
settings on the VMG for Internet access (Section 6.2 on page 74).
• Use the Cellular Backup screen to configure cellular WAN connection (Section 6.3 on page 83).
• Use the Advanced screen to enable or disable PTM over ADSL, Annex M/Annex J, and DSL PhyR
functions (Section 6.4 on page 89).
DSL
Table 9 WAN Setup Overview
LAYER-2 INTERFACE INTERNET CONNECTION
CONNECTION DSL LINK TYPE MODE ENCAPSULATION CONNECTION SETTINGS
ADSL/VDSL over
PTM
N/A Routing PPPoE PPP information, IPv4/IPv6 IP address,
routing feature, DNS server, VLAN,
and MTU
IPoE IPv4/IPv6 IP address, routing feature,
DNS server, VLAN, and MTU
Bridge N/A VLAN
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6.1.2 What You Need to Know
The following terms and concepts may help as you read this chapter.
WAN IP Address
The WAN IP address is an IP address for the VMG, which makes it accessible from an outside network. It is
used by the VMG to communicate with other devices in other networks. It can be static (fixed) or
dynamically assigned by the ISP each time the VMG tries to access the Internet.
If your ISP assigns you a static WAN IP address, they should also assign you the subnet mask and DNS
server IP address(es).
ATM
Asynchronous Transfer Mode (ATM) is a WAN networking technology that provides high-speed data
transfer. ATM uses fixed-size packets of information called cells. With ATM, a high QoS (Quality of Service)
can be guaranteed. ATM uses a connection-oriented model and establishes a virtual circuit (VC)
between Finding Out More
PTM
Packet Transfer Mode (PTM) is packet-oriented and supported by the VDSL2 standard. In PTM, packets
are encapsulated directly in the High-level Data Link Control (HDLC) frames. It is designed to provide a
low-overhead, transparent way of transporting packets over DSL links, as an alternative to ATM.
IPv6 Introduction
IPv6 (Internet Protocol version 6), is designed to enhance IP address size and features. The increase in
IPv6 address size to 128 bits (from the 32-bit IPv4 address) allows up to 3.4 x 1038 IP addresses. The VMG
can use IPv4/IPv6 dual stack to connect to IPv4 and IPv6 networks, and supports IPv6 rapid deployment
(6RD).
ADSL over ATM EoA Routing PPPoE/PPPoA ATM PVC configuration, PPP
information, IPv4/IPv6 IP address,
routing feature, DNS server, VLAN,
and MTU
IPoE/IPoA ATM PVC configuration, IPv4/IPv6 IP
address, routing feature, DNS server,
VLAN, and MTU
Bridge N/A ATM PVC configuration
Ethernet N/A Routing PPPoE PPP user name and password, WAN
IPv4/IPv6 IP address, routing feature,
DNS server, VLAN and MTU
IPoE WAN IPv4/IPv6 IP address, NAT, DNS
server and routing feature
Bridge N/A VLAN
Table 9 WAN Setup Overview
LAYER-2 INTERFACE INTERNET CONNECTION
CONNECTION DSL LINK TYPE MODE ENCAPSULATION CONNECTION SETTINGS
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IPv6 Addressing
The 128-bit IPv6 address is written as eight 16-bit hexadecimal blocks separated by colons (:). This is an
example IPv6 address 2001:0db8:1a2b:0015:0000:0000:1a2f:0000.
IPv6 addresses can be abbreviated in two ways:
• Leading zeros in a block can be omitted. So
2001:0db8:1a2b:0015:0000:0000:1a2f:0000 can be written as
2001:db8:1a2b:15:0:0:1a2f:0.
• Any number of consecutive blocks of zeros can be replaced by a double colon. A double
colon can only appear once in an IPv6 address. So
2001:0db8:0000:0000:1a2f:0000:0000:0015 can be written as
2001:0db8::1a2f:0000:0000:0015, 2001:0db8:0000:0000:1a2f::0015,
2001:db8::1a2f:0:0:15 or 2001:db8:0:0:1a2f::15.
IPv6 Prefix and Prefix Length
Similar to an IPv4 subnet mask, IPv6 uses an address prefix to represent the network address. An IPv6
prefix length specifies how many most significant bits (start from the left) in the address compose the
network address. The prefix length is written as “/x” where x is a number. For example,
2001:db8:1a2b:15::1a2f:0/32
means that the first 32 bits (2001:db8) is the subnet prefix.
IPv6 Subnet Masking
Both an IPv6 address and IPv6 subnet mask compose of 128-bit binary digits, which are divided into
eight 16-bit blocks and written in hexadecimal notation. Hexadecimal uses four bits for each character
(1 ~ 10, A ~ F). Each block’s 16 bits are then represented by four hexadecimal characters. For example,
FFFF:FFFF:FFFF:FFFF:FC00:0000:0000:0000.
IPv6 Rapid Deployment
Use IPv6 Rapid Deployment (6rd) when the local network uses IPv6 and the ISP has an IPv4 network.
When the VMG has an IPv4 WAN address and you set IPv4/IPv6 Mode to IPv4 Only, you can enable 6rd
to encapsulate IPv6 packets in IPv4 packets to cross the ISP’s IPv4 network.
The VMG generates a global IPv6 prefix from its IPv4 WAN address and tunnels IPv6 traffic to the ISP’s
Border Relay router (BR in the figure) to connect to the native IPv6 Internet. The local network can also
use IPv4 services. The VMG uses it’s configured IPv4 WAN IP to route IPv4 traffic to the IPv4 Internet.
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Figure 25 IPv6 Rapid Deployment
Dual Stack Lite
Use Dual Stack Lite when local network computers use IPv4 and the ISP has an IPv6 network. When the
VMG has an IPv6 WAN address and you set IPv4/IPv6 Mode to IPv6 Only, you can enable Dual Stack Lite
to use IPv4 computers and services.
The VMG tunnels IPv4 packets inside IPv6 encapsulation packets to the ISP’s Address Family Transition
Router (AFTR in the graphic) to connect to the IPv4 Internet. The local network can also use IPv6 services.
The VMG uses it’s configured IPv6 WAN IP to route IPv6 traffic to the IPv6 Internet.
Figure 26 Dual Stack Lite
DSL
DSL
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6.1.3 Before You Begin
You need to know your Internet access settings such as encapsulation and WAN IP address. Get this
information from your ISP.
6.2 The Broadband Screen
Use this screen to change your VMG’s Internet access settings. Click Network Setting > Broadband from
the menu. The summary table shows you the configured WAN services (connections) on the VMG.
Figure 27 Network Setting > Broadband
The following table describes the labels in this screen.
Table 10 Network Setting > Broadband
LABEL DESCRIPTION
Add New WAN
Interface
Click this button to create a new connection.
# This is the index number of the entry.
Name This is the service name of the connection.
Type This shows whether it is an ATM, a PTM or an Ethernet connection.
Mode This shows whether the connection is in routing or bridge mode.
Encapsulation This is the method of encapsulation used by this connection.
802.1p This indicates the 802.1p priority level assigned to traffic sent through this connection. This
displays N/A when there is no priority level assigned.
802.1q This indicates the VLAN ID number assigned to traffic sent through this connection. This displays
N/A when there is no VLAN ID number assigned.
Igmp Proxy This shows whether the VMG act as an IGMP proxy on this connection.
NAT This shows whether NAT is activated or not for this connection.
Default
Gateway
This shows whether the VMG use the WAN interface of this connection as the system default
gateway.
IPv6 This shows whether IPv6 is activated or not for this connection. IPv6 is not available when the
connection uses the bridging service.
MLD Proxy This shows whether Multicast Listener Discovery (MLD) is activated or not for this connection. MLD
is not available when the connection uses the bridging service.
Modify Click the Edit icon to configure the WAN connection.
Click the Delete icon to remove the WAN connection.
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6.2.1 Add/Edit Internet Connection
Click Add New WAN Interface in the Broadband screen or the Edit icon next to an existing WAN interface
to configure a WAN connection. The screen varies depending on the interface type, mode,
encapsulation, and IPv6/IPv4 mode you select.
6.2.1.1 Routing Mode
Use Routing mode if your ISP give you one IP address only and you want multiple computers to share an
Internet account.
The following example screen displays when you select the ADSL over ATM connection type, Routing
mode, and PPPoE encapsulation. The screen varies when you select other interface type,
encapsulation, and IPv6/IPv4 mode.
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Figure 28 Network Setting > Broadband > Add New WAN Interface/Edit (Routing Mode)
The following table describes the labels in this screen.
Table 11 Network Setting > Broadband > Add New WAN Interface/Edit (Routing Mode)
LABEL DESCRIPTION
General
Active Select Enable or Disable to activate or deactivate the interface.
Name Specify a descriptive name for this connection.
Type Select whether it is an ADSL/VDSL over PTM or ADSL over ATM connection.
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Mode Select Routing if your ISP give you one IP address only and you want multiple computers to share
an Internet account.
Encapsulation Select the method of encapsulation used by your ISP from the drop-down list box. This option is
available only when you select Routing in the Mode field.
The choices depend on the connection type you selected. If your connection type is ADSL/VDSL
over PTM, the choices are PPPoE and IPoE. If your connection type is ADSL over ATM, the choices
are PPPoE, PPPoA, IPoE and IPoA. If your connection type is Ethernet, the choices are PPPoE and
IPoE.
IPv4/IPv6 Mode Select IPv4 Only if you want the VMG to run IPv4 only.
Select IPv 4 IPv6 DualStack to allow the VMG to run IPv4 and IPv6 at the same time.
Select IPv6 Only if you want the VMG to run IPv6 only.
PPP Information (This is available only when you select PPPoE or PPPoA in the Mode field.)
PPP User Name Enter the user name exactly as your ISP assigned. If assigned a name in the form user@domain
where domain identifies a service name, then enter both components exactly as given.
PPP Password Enter the password associated with the user name above. Select password unmask to show your
entered password in plain text.
PPP Connection
Trigger
Select when to have the VMG establish the PPP connection.
Auto Connect - select this to not let the connection time out.
On Demand - select this to automatically bring up the connection when the VMG receives
packets destined for the Internet.
Idle Timeout This value specifies the time in minutes that elapses before the router automatically disconnects
from the PPPoE server.
This field is not available if you select Auto Connect in the PPP Connection Trigger field.
PPPoE
Passthrough
This field is available when you select PPPoE encapsulation.
In addition to the VMG’s built-in PPPoE client, you can enable PPPoE pass through to allow up to
ten hosts on the LAN to use PPPoE client software on their computers to connect to the ISP via
the VMG. Each host can have a separate account and a public WAN IP address.
PPPoE pass through is an alternative to NAT for application where NAT is not appropriate.
Disable PPPoE pass through if you do not need to allow hosts on the LAN to use PPPoE client
software on their computers to connect to the ISP.
IP Address (This is available only when you select IPv4 Only or IPv4 IPv6 DualStack in the IPv4/IPv6 Mode field.)
Obtain an IP
Address
Automatically
A static IP address is a fixed IP that your ISP gives you. A dynamic IP address is not fixed; the ISP
assigns you a different one each time you connect to the Internet. Select this if you have a
dynamic IP address.
Static IP Address Select this option If the ISP assigned a fixed IP address.
IP Address Enter the static IP address provided by your ISP.
Subnet Mask Enter the subnet mask provided by your ISP.
Gateway IP
Address
Enter the gateway IP address provided by your ISP.
ATM PVC Configuration (These fields appear when the Type is set to ADSL over ATM.)
VPI The valid range for the VPI is 0 to 255. Enter the VPI assigned to you.
VCI The valid range for the VCI is 32 to 65535 (0 to 31 is reserved for local management of ATM
traffic). Enter the VCI assigned to you.
Table 11 Network Setting > Broadband > Add New WAN Interface/Edit (Routing Mode) (continued)
LABEL DESCRIPTION
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Encapsulation Select the method of multiplexing used by your ISP from the drop-down list box. Choices are:
•LLC/SNAP-BRIDGING: In LCC encapsulation, bridged PDUs are encapsulated by identifying
the type of the bridged media in the SNAP header. This is available only when you select IPoE
or PPPoE in the Select DSL Link Type field.
•VC/MUX: In VC multiplexing, each protocol is carried on a single ATM virtual circuit (VC). To
transport multiple protocols, the VMG needs separate VCs. There is a binding between a VC
and the type of the network protocol carried on the VC. This reduces payload overhead
since there is no need to carry protocol information in each Protocol Data Unit (PDU)
payload.
Service
Category
Select UBR Without PCRfor applications that are non-time sensitive, such as e-mail.
Select CBR (Continuous Bit Rate) to specify fixed (always-on) bandwidth for voice or data traffic.
Select Non Realtime VBR (non real-time Variable Bit Rate) for connections that do not require
closely controlled delay and delay variation.
Select Realtime VBR (real-time Variable Bit Rate) for applications with bursty connections that
require closely controlled delay and delay variation.
Peak Cell
Rate [cells/s] Divide the DSL line rate (bps) by 424 (the size of an ATM cell) to find the Peak Cell Rate (PCR). This
is the maximum rate at which the sender can send cells. Type the PCR here.
Sustainable
Cell Rate The Sustain Cell Rate (SCR) sets the average cell rate (long-term) that can be transmitted. Type
the SCR, which must be less than the PCR. Note that system default is 0 cells/sec.
Maximum
Burst Size
[cells]
Maximum Burst Size (MBS) refers to the maximum number of cells that can be sent at the peak
rate. Type the MBS, which is less than 65535.
VLAN (These fields appear when the Type is set to ADSL/VDSL over PTM.)
Active Select Enable to activate VLAN on this WAN interface. Otherwise, select Disable to deactivate.
802.1p IEEE 802.1p defines up to 8 separate traffic types by inserting a tag into a MAC-layer frame that
contains bits to define class of service.
Select the IEEE 802.1p priority level (from 0 to 7) to add to traffic through this connection. The
greater the number, the higher the priority level.
802.1q Type the VLAN ID number (from 1 to 4094) for traffic through this connection.
MTU
MTU Enter the MTU (Maximum Transfer Unit) size for this traffic.
Routing Feature (This is available only when you select IPv4 Only or IPv4 IPv6 DualStack in the IPv4/IPv6 Mode field.)
NAT Enable Select this option to activate NAT on this connection.
Fullcone NAT
Enable
Select this option to enable full cone NAT on this connection. This field is available only when you
activate NAT. In full cone NAT, the VMG maps all outgoing packets from an internal IP address
and port to a single IP address and port on the external network. The VMG also maps packets
coming to that external IP address and port to the internal IP address and port.
IGMP Proxy
Enable
Internet Group Multicast Protocol (IGMP) is a network-layer protocol used to establish
membership in a Multicast group - it is not used to carry user data.
Select this option to have the VMG act as an IGMP proxy on this connection. This allows the VMG
to get subscribing information and maintain a joined member list for each multicast group. It can
reduce multicast traffic significantly.
Apply as Default
Gateway
Select this option to have the VMG use the WAN interface of this connection as the system
default gateway.
DNS Server (This is available only when you select IPv4 Only or IPv4 IPv6 DualStack in the IPv4/IPv6 Mode field.)
Select Obtain DNS Info Automically if you want the VMG to use the DNS server addresses
assigned by your ISP.
Select Use Following Static DNS Address if you want the VMG to use the DNS server addresses
you configure manually.
Table 11 Network Setting > Broadband > Add New WAN Interface/Edit (Routing Mode) (continued)
LABEL DESCRIPTION
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Primary DNS
Server
Enter the first DNS server address assigned by the ISP.
Secondary DNS
Server
Enter the second DNS server address assigned by the ISP.
Tunnel
The DS-Lite (Dual Stack Lite) fields display when you set the IPv4/IPv6 Mode field to IPv6 Only.
Enable Dual Stack Lite to let local computers use IPv4 through an ISP’s IPv6 network. See Dual Stack Lite on page 73
for more information.
Enabled DS-Lite This is available only when you select IPv6 Only in the IP v4 /IPv6 Mode field. Select Enable to let
local computers use IPv4 through an ISP’s IPv6 network.
DS-Lite Relay
Server IP
Specify the transition router’s IPv6 address.
6RD
The 6RD (IPv6 rapid deployment) fields display when you set the IPv6/IPv4 Mode field to IPv4 Only. See IPv6 Rapid
Deployment on page 72 for more information.
6RD Select Enable to tunnel IPv6 traffic from the local network through the ISP’s IPv4 network.
Select Manually Configur ed if you have the IPv4 address of the relay server. Otherwise, select
Automatically configured by DHCPC to have the VMG detect it automatically through DHCP.
The Automatically configured by DHCPC option is configurable only when you set the method of
encapsulation to IPoE.
Service Provider
IPv6 Prefix
Enter an IPv6 prefix for tunneling IPv6 traffic to the ISP’s border relay router and connecting to the
native IPv6 Internet.
IPv4 Mask
Length
Enter the subnet mask number (1~32) for the IPv4 network.
Border Relay
IPv4 Address
When you select Manually Configured, specify the relay server’s IPv4 address in this field.
DHCPC Options (This is available only when you select IPv4 Only or IPv4 IPv6 DualStack in the IPv4/IPv6 Mode field.)
Request Options Select Option 42 to have the VMG get the NTP server which is available to the client.
Select Option 43 to have the VMG automatically add vendor specific information in the DHCP
packets to request the vendor specific options from the DHCP server.
Select Option 121 to have the VMG push static routes to clients.
Sent Options
option 60 Select this and enter the device identity you want the VMG to add in the DHCP discovery
packets that go to the DHCP server.
Vendor ID Enter the Vendor Class Identifier, such as the type of the hardware or firmware.
option 61 Select this and enter any string that identifies the device.
IAID Enter the Identity Association Identifier (IAID) of the device, for example, the WAN connection
index number.
DUID Enter the hardware type, a time value and the MAC address of the device.
option 125 Select this to have the VMG automatically generate and add vendor specific parameters in the
DHCP discovery packets that go to the DHCP server.
IPv6 Address (This is available only when you select IPv4 IPv6 DualStack or IPv6 Only in the IPv4/IPv6 Mode field.)
Obtain an IPv6
Address
Automatically
Select Obtain an IPv6 Address Automatically if you want to have the VMG use the IPv6 prefix
from the connected router’s Router Advertisement (RA) to generate an IPv6 address.
Table 11 Network Setting > Broadband > Add New WAN Interface/Edit (Routing Mode) (continued)
LABEL DESCRIPTION
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6.2.1.2 Bridge Mode
Click the Add new WAN Interface in the Network Setting > Broadband screen or the Edit icon next to the
connection you want to configure. Select Bridge as the encapsulation mode. The screen varies
depending on the interface type you select.
If you select ADSL/VDSL over PTM or Ethernet as the interface type, the following screen appears.
Static IPv6
Address
Select Static IPv6 Address if you have a fixed IPv6 address assigned by your ISP. When you select
this, the following fields appear.
IPv6 Address Enter an IPv6 IP address that your ISP gave to you for this WAN interface.
Prefix Length Enter the address prefix length to specify how many most significant bits in an IPv6 address
compose the network address.
IPv6 Default
Gateway Enter the IP address of the next-hop gateway. The gateway is a router or switch on the same
segment as your VMG's interface(s). The gateway helps forward packets to their destinations.
IPv6 Routing Feature (This is available only when you select IPv4 IPv6 DualStack or IPv6 Only in the IPv4/IPv6 Mode
field. You can enable IPv6 routing features in the following section.)
MLD Proxy
Enable
Select this checkbox to have the VMG act as an MLD proxy on this connection. This allows the
VMG to get subscription information and maintain a joined member list for each multicast
group. It can reduce multicast traffic significantly.
Apply as Default
Gateway
Select this option to have the VMG use the WAN interface of this connection as the system
default gateway.
IPv6 DNS Server (This is available only when you select IPv4 IPv6 DualStack or IPv6 Only in the IPv4/IPv6 Mode field.
Configure the IPv6 DNS server in the following section.
Obtain IPv6 DNS
Info
Automatically
Select Obtain IPv6 DNS Info Automatically to have the VMG get the IPv6 DNS server addresses
from the ISP automatically.
Use Following
Static IPv6 DNS
Address
Select Use Following Static IPv6 DNS Address to have the VMG use the IPv6 DNS server addresses
you configure manually.
Primary DNS
Server
Enter the first IPv6 DNS server address assigned by the ISP.
Secondary DNS
Server
Enter the second IPv6 DNS server address assigned by the ISP.
Table 11 Network Setting > Broadband > Add New WAN Interface/Edit (Routing Mode) (continued)
LABEL DESCRIPTION
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Figure 29 Network Setting > Broadband > Add New WAN Interface/Edit (ADSL/VDSL over PTM -Bridge
Mode)
The following table describes the fields in this screen.
If you select ADSL over ATM as the interface type, the following screen appears.
Table 12 Network Setting > Broadband > Add New WAN Interface/Edit (ADSL/VDSL over PTM -Bridge or
Ethernet Mode)
LABEL DESCRIPTION
General
Active Select Enable or Disable to activate or deactivate the interface.
Name Enter a service name of the connection.
Type Select ADSL/VDSL over PTM as the interface that you want to configure. The VMG uses the VDSL
technology for data transmission over the DSL port.
Mode Select Bridge when your ISP provides you more than one IP address and you want the connected
computers to get individual IP address from ISP’s DHCP server directly. If you select Bridge, you
cannot use routing functions, such as QoS, Firewall, DHCP server and NAT on traffic from the
selected LAN port(s).
VLAN This section is available only when you select ADSL/VDS L over PTM in the Type field.
Active Select Enable to activate VLAN on this WAN interface. Otherwise, select Disable to deactivate.
802.1p IEEE 802.1p defines up to 8 separate traffic types by inserting a tag into a MAC-layer frame that
contains bits to define class of service.
Select the IEEE 802.1p priority level (from 0 to 7) to add to traffic through this connection. The greater
the number, the higher the priority level.
802.1q Type the VLAN ID number (from 0 to 4094) for traffic through this connection.
OK Click OK to save your changes.
Cancel Click Cancel to exit this screen without saving.
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Figure 30 Network Setting > Broadband > Add New WAN Interface/Edit (ADSL over ATM-Bridge Mode)
The following table describes the fields in this screen.
Table 13 Network Setting > Broadband > Add New WAN Interface/Edit (ADSL over ATM-Bridge Mode)
LABEL DESCRIPTION
General
Active Select Enable or Disable to activate or deactivate the interface.
Name Enter a service name of the connection.
Type Select ADSL over ATM as the interface that you want to configure. The VMG uses the ADSL
technology for data transmission over the DSL port.
Mode Select Bridge when your ISP provides you more than one IP address and you want the
connected computers to get individual IP address from ISP’s DHCP server directly. If you select
Bridge, you cannot use routing functions, such as QoS, Firewall, DHCP server and NAT on traffic
from the selected LAN port(s).
ATM PVC Configuration (These fields appear when the Type is set to ADSL over ATM.)
VPI The valid range for the VPI is 0 to 255. Enter the VPI assigned to you.
VCI The valid range for the VCI is 32 to 65535 (0 to 31 is reserved for local management of ATM
traffic). Enter the VCI assigned to you.
Encapsulation Select the method of multiplexing used by your ISP from the drop-down list box. Choices are:
• LLC/SNAP-BRIDGING: In LCC encapsulation, bridged PDUs are encapsulated by identifying the
type of the bridged media in the SNAP header. This is available only when you select IPoE or
PPPoE in the Encapsulation field.
• VC/MUX: In VC multiplexing, each protocol is carried on a single ATM virtual circuit (VC). To
transport multiple protocols, the VMG needs separate VCs. There is a binding between a VC
and the type of the network protocol carried on the VC. This reduces payload overhead since
there is no need to carry protocol information in each Protocol Data Unit (PDU) payload.
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6.3 The Cellular Backup Screen
The USB port (at the side panel of the VMG) allows you to attach a cellular dongle to wirelessly connect
to a cellular network for Internet access. You can have the VMG use the cellular WAN connection as a
backup. Disconnect the DSL and Ethernet WAN ports to use the cellular dongle as your primary WAN
connection. The VMG automatically uses a wired WAN connection when available.
Figure 31 Internet Access Application: Cellular WAN
Service
Category
Select UBR Without PCR for applications that are non-time sensitive, such as e-mail.
Select CBR (Continuous Bit Rate) to specify fixed (always-on) bandwidth for voice or data traffic.
Select Non Realtime VBR (non real-time Variable Bit Rate) for connections that do not require
closely controlled delay and delay variation.
Select Realtime VBR (real-time Variable Bit Rate) for applications with bursty connections that
require closely controlled delay and delay variation.
Peak Cell
Rate [cells/s] Divide the DSL line rate (bps) by 424 (the size of an ATM cell) to find the Peak Cell Rate (PCR). This
is the maximum rate at which the sender can send cells. Type the PCR here.
Sustainable
Cell Rate The Sustain Cell Rate (SCR) sets the average cell rate (long-term) that can be transmitted. Type
the SCR, which must be less than the PCR. Note that system default is 0 cells/sec.
Maximum
Burst Size
[cells]
Maximum Burst Size (MBS) refers to the maximum number of cells that can be sent at the peak
rate. Type the MBS, which is less than 65535.
VLAN
Active Select Enable to activate VLAN on this WAN interface. Otherwise, select Disable to deactivate.
802.1p IEEE 802.1p defines up to 8 separate traffic types by inserting a tag into a MAC-layer frame that
contains bits to define class of service.
Select the IEEE 802.1p priority level (from 0 to 7) to add to traffic through this connection. The
greater the number, the higher the priority level.
802.1q Type the VLAN ID number (from 0 to 4094) for traffic through this connection.
OK Click OK to save your changes.
Cancel Click Cancel to exit this screen without saving.
Table 13 Network Setting > Broadband > Add New WAN Interface/Edit (ADSL over ATM-Bridge Mode)
(continued)
LABEL DESCRIPTION
DSL
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Use this screen to configure your cellular settings. Click Network Setting > Broadband > Cellular Backup.
Chapter 6 Broadband
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Note: The actual data rate you obtain varies depending on the cellular card you use, the
signal strength to the service provider’s base station, and so on.
Figure 32 Network Setting > Broadband > Cellular Backup
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The following table describes the labels in this screen.
Table 14 Network Setting > Broadband > cellular Backup
LABEL DESCRIPTION
General
Cellular Backup Select Enable to have the VMG use the cellular connection as your WAN or a backup when the
wired WAN connection fails.
Ping Check Select Enable if you want the VMG to ping check the connection status of your WAN. You can
configure the frequency of the ping check and number of consecutive failures before triggering
cellular backup.
Check Cycle Enter the frequency of the ping check in this field.
Consecutive Fail Enter how many consecutive failures are required before cellular backup is triggered.
Ping Default
Gateway
Select this to have the VMG ping the WAN interface’s default gateway IP address.
Ping Host Select this to have the VMG ping the particular host name or IP address you typed in this field.
Cellular Connection Settings
Card
description
This field displays the manufacturer and model name of your cellular card if you inserted one in
the VMG. Otherwise, it displays N/A.
Username Type the user name (of up to 64 ASCII printable characters) given to you by your service
provider.
Password Type the password (of up to 64 ASCII printable characters) associated with the user name
above.
Authentication The VMG supports PAP (Password Authentication Protocol) and CHAP (Challenge Handshake
Authentication Protocol). CHAP is more secure than PAP; however, PAP is readily available on
more platforms.
Use the drop-down list box to select an authentication protocol for outgoing calls. Options
are:
AUTO - Your VMG accepts either CHAP or PAP when requested by this remote node.
CHAP - Your VMG accepts CHAP only.
PAP - Your VMG accepts PAP only.
PIN A PIN (Personal Identification Number) code is a key to a cellular card. Without the PIN code,
you cannot use the cellular card.
If your ISP enabled PIN code authentication, enter the 4-digit PIN code (0000 for example)
provided by your ISP. If you enter the PIN code incorrectly, the cellular card may be blocked by
your ISP and you cannot use the account to access the Internet.
If your ISP disabled PIN code authentication, leave this field blank.
Dial string Enter the phone number (dial string) used to dial up a connection to your service provider’s base
station. Your ISP should provide the phone number.
For example, *99# is the dial string to establish a GPRS or cellular connection in Taiwan.
APN Enter the APN (Access Point Name) provided by your service provider. Connections with
different APNs may provide different services (such as Internet access or MMS (Multi-Media
Messaging Service)) and charge method.
You can enter up to 32 ASCII printable characters. Spaces are allowed.
Connection Select Nailed UP if you do not want the connection to time out.
Select on Demand if you do not want the connection up all the time and specify an idle time-
out in the Max Idle Timeout field.
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Max Idle
Timeout This value specifies the time in minutes that elapses before the VMG automatically disconnects
from the ISP.
Obtain an IP
Address
Automatically
Select this option if your ISP did not assign you a fixed IP address.
Use the
following static
IP address
Select this option if the ISP assigned a fixed IP address.
IP Address Enter your WAN IP address in this field if you selected Use the following static IP address.
Subnet Mask Enter the subnet mask of the IP address.
Obtain DNS info
Dynamically
Select this to have the VMG get the DNS server addresses from the ISP automatically.
Use the
following static
DNS IP address
Select this to have the VMG use the DNS server addresses you configure manually.
Primary DNS
server Enter the first DNS server address assigned by the ISP.
Secondary
DNS server Enter the second DNS server address assigned by the ISP.
Enable E-mail
Notification
Select this to enable the e-mail notification function. The VMG will e-mail you a notification when
the cellular connection is up.
Mail
Account Select an e-mail address you have configured in Maintenance > Email Notification. The VMG
uses the corresponding mail server to send notifications.
You must have configured a mail server already in the Maintenance > Email Notification screen.
Cellular
Backup E-
mail Title
Type a title that you want to be in the subject line of the e-mail notifications that the VMG sends.
Send
Notification
to E-mail
Notifications are sent to the e-mail address specified in this field. If this field is left blank,
notifications cannot be sent via e-mail.
Advanced Click this to show the advanced cellular backup settings.
Budget Setup
Enable Budget
Control
Select Enable to set a monthly limit for the user account of the installed cellular card. You can set
a limit on the total traffic and/or call time. The VMG takes the actions you specified when a limit
is exceeded during the month.
Time Budget Select this and specify the amount of time (in hours) that the cellular connection can be used
within one month. If you change the value after you configure and enable budget control, the
VMG resets the statistics.
Data Budget
(Mbytes)
Select this and specify how much downstream and/or upstream data (in Mega bytes) can be
transmitted via the cellular connection within one month.
Select Download/Upload to set a limit on the total traffic in both directions.
Select Download to set a limit on the downstream traffic (from the ISP to the VMG).
Select Upload to set a limit on the upstream traffic (from the VMG to the ISP).
If you change the value after you configure and enable budget control, the VMG resets the
statistics.
Table 14 Network Setting > Broadband > cellular Backup (continued)
LABEL DESCRIPTION
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Data Budget
(kPackets)
Select this and specify how much downstream and/or upstream data (in k Packets) can be
transmitted via the cellular connection within one month.
Select Download/Upload to set a limit on the total traffic in both directions.
Select Download to set a limit on the downstream traffic (from the ISP to the VMG).
Select Upload to set a limit on the upstream traffic (from the VMG to the ISP).
If you change the value after you configure and enable budget control, the VMG resets the
statistics.
Reset all budget
counters on
Select the date on which the VMG resets the budget every month. Select last if you want the
VMG to reset the budget on the last day of the month. Select specific and enter the number of
the date you want the VMG to reset the budget
Reset time and
data budget
counters
Click this button to reset the time and data budgets immediately. The count starts over with the
cellular connection’s full configured monthly time and data budgets. This does not affect the
normal monthly budget restart; so if you configured the time and data budget counters to reset
on the second day of the month and you use this button on the first, the time and data budget
counters will still reset on the second.
Actions before
over budget
Specify the actions the VMG takes before the time or data limit exceeds.
Enable % of time
budget/data
budget
(Mbytes)/data
budget
(kPackets)
Select Enable and enter a number from 1 to 99 in the percentage fields. If you change the value
after you configure and enable budget control, the VMG resets the statistics.
Actions when
over budget
Specify the actions the VMG takes when the time or data limit is exceeded.
Current Cellular
connection
Select Keep to maintain an existing cellular connection or Drop to disconnect it.
Actions
Enable E-mail
Notification
Select Enable to enable the e-mail notification function. The VMG will e-mail you a notification
when there over budget occurs.
Mail
Account Select an e-mail address you have configured in Maintenance > Email Notification. The VMG
uses the corresponding mail server to send notifications.
You must have configured a mail server already in the Maintenance > Email Notification screen.
Cellular
Backup E-
mail Title
Type a title that you want to be in the subject line of the e-mail notifications that the VMG sends.
Send
Notification
to E-mail
Notifications are sent to the e-mail address specified in this field. If this field is left blank,
notifications cannot be sent via e-mail.
Enable Log Select this to activate the logging function at the interval you set in this field.
Interval Enter the interval of how many minutes you want the VMG to e-mail you.
Basic Click this to hide the advanced settings of cellular backup.
Apply Click Apply to save your changes back to the VMG.
Cancel Click Cancel to return to the previous configuration.
Table 14 Network Setting > Broadband > cellular Backup (continued)
LABEL DESCRIPTION
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6.4 The Advanced Screen
Use the Advanced screen to enable or disable Annex M, DSL PhyR, and SRA (Seamless Rate Adaptation)
functions. The VMG supports the PhyR retransmission scheme. PhyR is a retransmission scheme designed
to provide protection against noise on the DSL line. It improves voice, video and data transmission
resilience by utilizing a retransmission buffer.
ITU-T G.993.2 standard defines a wide range of settings for various parameters, some of which are
encompassed in profiles as shown in the next table.
Click Network Setting > Broadband > Advanced to display the following screen.
Figure 33 Network Setting > Broadband > Advanced
Table 15 VDSL Profiles
PROFILE BANDWIDTH
(MHZ)
NUMBER OF
DOWNSTREAM
CARRIERS
CARRIER
BANDWIDTH
(KHZ) POWER (DBM)
MAX.
DOWNSTREAM
THROUGHPUT
(MBIT/S)
8a 8.832 2048 4.3125 17.5 50
8b 8.832 2048 4.3125 20.5 50
8c 8.5 1972 4.3125 11.5 50
8d 8.832 2048 4.3125 14.5 50
12a 12 2783 4.3125 14.5 68
12b 12 2783 4.3125 14.5 68
17a 17.664 4096 4.3125 14.5 100
30a 30 3479 8.625 14.5 200
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The following table describes the labels in this screen.
Table 16 Network Setting > Broadband > Advanced
LABEL DESCRIPTION
DSL Capabilities
PhyR US/DS Enable or disable PhyR US (upstream) for upstream transmission to the WAN. PhyR US should be
enabled if data being transmitted upstream is sensitive to noise. However, enabling PhyR US can
decrease the US line rate. Enabling or disabling PhyR will require the CPE to retrain. For PhyR to
function, the DSLAM must also support PhyR and have it enabled.
Enable or disable PhyR DS (downstream) for downstream transmission from the WAN. PhyR DS
should be enabled if data being transmitted downstream is sensitive to noise. However,
enabling PhyR DS can decrease the DS line rate. Enabling or disabling PhyR will require the CPE
to retrain. For PhyR to function, the DSLAM must also support PhyR and have it enabled.
Bitswap Select Enable to allow the VMG to adapt to line changes when you are using G.dmt.
Bit-swapping is a way of keeping the line more stable by constantly monitoring and redistributing
bits between channels.
SRA Enable or disable Seamless Rate Adaption (SRA). Select Enable to have the VMG automatically
adjust the connection’s data rate according to line conditions without interrupting service.
DSL Modulation
G.Dmt ITU G.992.1 (better known as G.dmt) is an ITU standard for ADSL using discrete multitone
modulation. G.dmt full-rate ADSL expands the usable bandwidth of existing copper telephone
lines, delivering high-speed data communications at rates up to 8 Mbit/s downstream and 1.3
Mbit/s upstream.
G.lite ITU G.992.2 (better known as G.lite) is an ITU standard for ADSL using discrete multitone
modulation. G.lite does not strictly require the use of DSL filters, but like all variants of ADSL
generally functions better with splitters.
T1.413 ANSI T1.413 is a technical standard that defines the requirements for the single asymmetric
digital subscriber line (ADSL) for the interface between the telecommunications network and
the customer installation in terms of their interaction and electrical characteristics.
ADSL2 It optionally extends the capability of basic ADSL in data rates to 12 Mbit/s downstream and,
depending on Annex version, up to 3.5 Mbit/s upstream (with a mandatory capability of ADSL2
transceivers of 8 Mbit/s downstream and 800 kbit/s upstream).
AnnexL Annex L is an optional specification in the ITU-T ADSL2 recommendation G.992.3 titled Specific
requirements for a Reach Extended ADSL2 (READSL2) system operating in the frequency band
above POTS, therefore it is often referred to as Reach Extended ADSL2 or READSL2.The main
difference between this specification and commonly deployed Annex A is the maximum
distance that can be used. The power of the lower frequencies used for transmitting data is
boosted up to increase the reach of this signal up to 7 kilometers (23,000 ft).
ADSL2+ ADSL2+ extends the capability of basic ADSL by doubling the number of downstream channels.
The data rates can be as high as 24 Mbit/s downstream and up to 1.4 Mbit/s upstream
depending on the distance from the DSLAM to the customer's premises.
Annex M Annex M is an optional specification in ITU-T recommendations G.992.3 (ADSL2) and G.992.5
(ADSL2+), also referred to as ADSL2 M and ADSL2+ M. This specification extends the capability of
commonly deployed Annex A by more than doubling the number of upstream bits. The data
rates can be as high as 12 or 24 Mbit/s downstream and 3 Mbit/s upstream depending on the
distance from the DSLAM to the customer's premises.
VDSL2 VDSL2 (Very High Speed Digital Subscriber Line 2) is the second generation of the VDSL standard
(which is currently denoted VDSL1). VDSL2 allows a frequency band of up to 30MHz and
transmission rates of up to 100 Mbps in each direction. VDSL2 is defined in G.993.2.
VDSL Profile
VDSL2 profiles differ in the width of the frequency band used to transmit the broadband signal. Profiles that use a
wider frequency band can deliver higher maximum speeds.
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6.5 Technical Reference
The following section contains additional technical information about the VMG features described in
this chapter.
Encapsulation
Be sure to use the encapsulation method required by your ISP. The VMG can work in bridge mode or
routing mode. When the VMG is in routing mode, it supports the following methods.
IP over Ethernet
IP over Ethernet (IPoE) is an alternative to PPPoE. IP packets are being delivered across an Ethernet
network, without using PPP encapsulation. They are routed between the Ethernet interface and the
WAN interface and then formatted so that they can be understood in a bridged environment. For
instance, it encapsulates routed Ethernet frames into bridged Ethernet cells.
PPP over ATM (PPPoA)
PPPoA stands for Point to Point Protocol over ATM Adaptation Layer 5 (AAL5). A PPPoA connection
functions like a dial-up Internet connection. The VMG encapsulates the PPP session based on RFC1483
and sends it through an ATM PVC (Permanent Virtual Circuit) to the Internet Service Provider’s (ISP)
DSLAM (digital access multiplexer). Please refer to RFC 2364 for more information on PPPoA. Refer to RFC
1661 for more information on PPP.
PPP over Ethernet (PPPoE)
Point-to-Point Protocol over Ethernet (PPPoE) provides access control and billing functionality in a
manner similar to dial-up services using PPP. PPPoE is an IETF standard (RFC 2516) specifying how a
personal computer (PC) interacts with a broadband modem (DSL, cable, wireless, etc.) connection.
For the service provider, PPPoE offers an access and authentication method that works with existing
access control systems (for example RADIUS).
One of the benefits of PPPoE is the ability to let you access one of multiple network services, a function
known as dynamic service selection. This enables the service provider to easily create and offer new IP
services for individuals.
8a, 8b, 8c, 8d,
12a, 12b, 17a,
US0
The G.993.2 VDSL standard defines a wide range of profiles that can be used in different VDSL
deployment settings, such as in a central office, a street cabinet or a building.
The VMG must comply with at least one profile specified in G.993.2. but compliance with more
than one profile is allowed.
Apply Click Apply to save your changes back to the VMG.
Cancel Click Cancel to return to the previous configuration.
Table 16 Network Setting > Broadband > Advanced (continued)
LABEL DESCRIPTION
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Operationally, PPPoE saves significant effort for both you and the ISP or carrier, as it requires no specific
configuration of the broadband modem at the customer site.
By implementing PPPoE directly on the VMG (rather than individual computers), the computers on the
LAN do not need PPPoE software installed, since the VMG does that part of the task. Furthermore, with
NAT, all of the LANs’ computers will have access.
RFC 1483
RFC 1483 describes two methods for Multiprotocol Encapsulation over ATM Adaptation Layer 5 (AAL5).
The first method allows multiplexing of multiple protocols over a single ATM virtual circuit (LLC-based
multiplexing) and the second method assumes that each protocol is carried over a separate ATM virtual
circuit (VC-based multiplexing). Please refer to RFC 1483 for more detailed information.
Multiplexing
There are two conventions to identify what protocols the virtual circuit (VC) is carrying. Be sure to use the
multiplexing method required by your ISP.
VC-based Multiplexing
In this case, by prior mutual agreement, each protocol is assigned to a specific virtual circuit; for
example, VC1 carries IP, etc. VC-based multiplexing may be dominant in environments where dynamic
creation of large numbers of ATM VCs is fast and economical.
LLC-based Multiplexing
In this case one VC carries multiple protocols with protocol identifying information being contained in
each packet header. Despite the extra bandwidth and processing overhead, this method may be
advantageous if it is not practical to have a separate VC for each carried protocol, for example, if
charging heavily depends on the number of simultaneous VCs.
Traffic Shaping
Traffic Shaping is an agreement between the carrier and the subscriber to regulate the average rate
and fluctuations of data transmission over an ATM network. This agreement helps eliminate congestion,
which is important for transmission of real time data such as audio and video connections.
Peak Cell Rate (PCR) is the maximum rate at which the sender can send cells. This parameter may be
lower (but not higher) than the maximum line speed. 1 ATM cell is 53 bytes (424 bits), so a maximum
speed of 832Kbps gives a maximum PCR of 1962 cells/sec. This rate is not guaranteed because it is
dependent on the line speed.
Sustained Cell Rate (SCR) is the mean cell rate of each bursty traffic source. It specifies the maximum
average rate at which cells can be sent over the virtual connection. SCR may not be greater than the
PCR.
Maximum Burst Size (MBS) is the maximum number of cells that can be sent at the PCR. After MBS is
reached, cell rates fall below SCR until cell rate averages to the SCR again. At this time, more cells (up to
the MBS) can be sent at the PCR again.
If the PCR, SCR or MBS is set to the default of "0", the system will assign a maximum value that correlates
to your upstream line rate.
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The following figure illustrates the relationship between PCR, SCR and MBS.
Figure 34 Example of Traffic Shaping
ATM Traffic Classes
These are the basic ATM traffic classes defined by the ATM Forum Traffic Management 4.0 Specification.
Constant Bit Rate (CBR)
Constant Bit Rate (CBR) provides fixed bandwidth that is always available even if no data is being sent.
CBR traffic is generally time-sensitive (doesn't tolerate delay). CBR is used for connections that
continuously require a specific amount of bandwidth. A PCR is specified and if traffic exceeds this rate,
cells may be dropped. Examples of connections that need CBR would be high-resolution video and
voice.
Variable Bit Rate (VBR)
The Variable Bit Rate (VBR) ATM traffic class is used with bursty connections. Connections that use the
Variable Bit Rate (VBR) traffic class can be grouped into real time (VBR-RT) or non-real time (VBR-nRT)
connections.
The VBR-RT (real-time Variable Bit Rate) type is used with bursty connections that require closely
controlled delay and delay variation. It also provides a fixed amount of bandwidth (a PCR is specified)
but is only available when data is being sent. An example of an VBR-RT connection would be video
conferencing. Video conferencing requires real-time data transfers and the bandwidth requirement
varies in proportion to the video image's changing dynamics.
The VBR-nRT (non real-time Variable Bit Rate) type is used with bursty connections that do not require
closely controlled delay and delay variation. It is commonly used for "bursty" traffic typical on LANs. PCR
and MBS define the burst levels, SCR defines the minimum level. An example of an VBR-nRT connection
would be non-time sensitive data file transfers.
Unspecified Bit Rate (UBR)
The Unspecified Bit Rate (UBR) ATM traffic class is for bursty data transfers. However, UBR doesn't
guarantee any bandwidth and only delivers traffic when the network has spare bandwidth. An example
application is background file transfer.
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IP Address Assignment
A static IP is a fixed IP that your ISP gives you. A dynamic IP is not fixed; the ISP assigns you a different one
each time. The Single User Account feature can be enabled or disabled if you have either a dynamic or
static IP. However the encapsulation method assigned influences your choices for IP address and
default gateway.
Introduction to VLANs
A Virtual Local Area Network (VLAN) allows a physical network to be partitioned into multiple logical
networks. Devices on a logical network belong to one group. A device can belong to more than one
group. With VLAN, a device cannot directly talk to or hear from devices that are not in the same
group(s); the traffic must first go through a router.
In Multi-Tenant Unit (MTU) applications, VLAN is vital in providing isolation and security among the
subscribers. When properly configured, VLAN prevents one subscriber from accessing the network
resources of another on the same LAN, thus a user will not see the printers and hard disks of another user
in the same building.
VLAN also increases network performance by limiting broadcasts to a smaller and more manageable
logical broadcast domain. In traditional switched environments, all broadcast packets go to each and
every individual port. With VLAN, all broadcasts are confined to a specific broadcast domain.
Introduction to IEEE 802.1Q Tagged VLAN
A tagged VLAN uses an explicit tag (VLAN ID) in the MAC header to identify the VLAN membership of a
frame across bridges - they are not confined to the switch on which they were created. The VLANs can
be created statically by hand or dynamically through GVRP. The VLAN ID associates a frame with a
specific VLAN and provides the information that switches need to process the frame across the network.
A tagged frame is four bytes longer than an untagged frame and contains two bytes of TPID (Tag
Protocol Identifier), residing within the type/length field of the Ethernet frame) and two bytes of TCI (Tag
Control Information), starts after the source address field of the Ethernet frame).
The CFI (Canonical Format Indicator) is a single-bit flag, always set to zero for Ethernet switches. If a
frame received at an Ethernet port has a CFI set to 1, then that frame should not be forwarded as it is to
an untagged port. The remaining twelve bits define the VLAN ID, giving a possible maximum number of
4,096 VLANs. Note that user priority and VLAN ID are independent of each other. A frame with VID
(VLAN Identifier) of null (0) is called a priority frame, meaning that only the priority level is significant and
the default VID of the ingress port is given as the VID of the frame. Of the 4096 possible VIDs, a VID of 0 is
used to identify priority frames and value 4095 (FFF) is reserved, so the maximum possible VLAN
configurations are 4,094.
Multicast
IP packets are transmitted in either one of two ways - Unicast (1 sender - 1 recipient) or Broadcast (1
sender - everybody on the network). Multicast delivers IP packets to a group of hosts on the network -
not everybody and not just 1.
TPID
2 Bytes
User Priority
3 Bits
CFI
1 Bit
VLAN ID
12 Bits
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Internet Group Multicast Protocol (IGMP) is a network-layer protocol used to establish membership in a
Multicast group - it is not used to carry user data. IGMP version 2 (RFC 2236) is an improvement over
version 1 (RFC 1112) but IGMP version 1 is still in wide use. If you would like to read more detailed
information about interoperability between IGMP version 2 and version 1, please see sections 4 and 5 of
RFC 2236. The class D IP address is used to identify host groups and can be in the range 224.0.0.0 to
239.255.255.255. The address 224.0.0.0 is not assigned to any group and is used by IP multicast
computers. The address 224.0.0.1 is used for query messages and is assigned to the permanent group of
all IP hosts (including gateways). All hosts must join the 224.0.0.1 group in order to participate in IGMP.
The address 224.0.0.2 is assigned to the multicast routers group.
At start up, the VMG queries all directly connected networks to gather group membership. After that,
the VMG periodically updates this information.
DNS Server Address Assignment
Use Domain Name System (DNS) to map a domain name to its corresponding IP address and vice versa,
for instance, the IP address of www.zyxel.com is 204.217.0.2. The DNS server is extremely important
because without it, you must know the IP address of a computer before you can access it.
The VMG can get the DNS server addresses in the following ways.
1The ISP tells you the DNS server addresses, usually in the form of an information sheet, when you sign up.
If your ISP gives you DNS server addresses, manually enter them in the DNS server fields.
2If your ISP dynamically assigns the DNS server IP addresses (along with the VMG’s WAN IP address), set
the DNS server fields to get the DNS server address from the ISP.
IPv6 Addressing
The 128-bit IPv6 address is written as eight 16-bit hexadecimal blocks separated by colons (:). This is an
example IPv6 address 2001:0db8:1a2b:0015:0000:0000:1a2f:0000.
IPv6 addresses can be abbreviated in two ways:
• Leading zeros in a block can be omitted. So 2001:0db8:1a2b:0015:0000:0000:1a2f:0000 can be
written as 2001:db8:1a2b:15:0:0:1a2f:0.
• Any number of consecutive blocks of zeros can be replaced by a double colon. A double colon can
only appear once in an IPv6 address. So 2001:0db8:0000:0000:1a2f:0000:0000:0015 can be
written as 2001:0db8::1a2f:0000:0000:0015, 2001:0db8:0000:0000:1a2f::0015,
2001:db8::1a2f:0:0:15 or 2001:db8:0:0:1a2f::15.
IPv6 Prefix and Prefix Length
Similar to an IPv4 subnet mask, IPv6 uses an address prefix to represent the network address. An IPv6
prefix length specifies how many most significant bits (start from the left) in the address compose the
network address. The prefix length is written as “/x” where x is a number. For example,
2001:db8:1a2b:15::1a2f:0/32
means that the first 32 bits (2001:db8) is the subnet prefix.
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CHAPTER 7
Wireless
7.1 Overview
This chapter describes the VMG’s Network Setting > Wireless screens. Use these screens to set up your
VMG’s wireless connection.
7.1.1 What You Can Do in this Chapter
This section describes the VMG’s Wireless screens. Use these screens to set up your VMG’s wireless
connection.
• Use the General screen to enable the Wireless LAN, enter the SSID and select the wireless security
mode (Section 7.2 on page 97).
• Use the Guest/More AP screen to set up multiple wireless networks on your VMG (Section 7.3 on page
101).
• Use the MAC Authentication screen to low or deny wireless clients based on their MAC addresses from
connecting to the VMG (Section 7.4 on page 104).
• Use the WPS screen to enable or disable WPS, view or generate a security PIN (Personal Identification
Number) (Section 7.5 on page 105).
• Use the WMM screen to enable Wi-Fi MultiMedia (WMM) to ensure quality of service in wireless
networks for multimedia applications (Section 7.6 on page 107).
• Use the Others screen to configure wireless advanced features, such as the RTS/CTS Threshold
(Section 7.7 on page 108).
• Use the Channel Status screen to scan wireless LAN channel noises and view the results (Section 7.8 on
page 109).
7.1.2 What You Need to Know
Wireless Basics
“Wireless” is essentially radio communication. In the same way that walkie-talkie radios send and
receive information over the airwowaves, wireless networking devices exchange information with one
another. A wireless networking device is just like a radio that lets your computer exchange information
with radios attached to other computers. Like walkie-talkies, most wireless networking devices operate
at radio frequency bands that are open to the public and do not require a license to use. However,
wireless networking is different from that of most traditional radio communications in that there a
number of wireless networking standards available with different methods of data encryption.
Finding Out More
See Section 7.9 on page 110 for advanced technical information on wireless networks.
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7.2 The General Screen
Use this screen to enable the Wireless LAN, enter the SSID and select the wireless security mode.
Note: If you are configuring the VMG from a computer connected to the wireless LAN and
you change the VMG’s SSID, channel or security settings, you will lose your wireless
connection when you press Apply to confirm. You must then change the wireless
settings of your computer to match the VMG’s new settings.
Click Network Setting > Wireless to open the General screen.
Figure 35 Network Setting > Wireless > General
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The following table describes the general wireless LAN labels in this screen.
7.2.1 No Security
Select No Security to allow wireless stations to communicate with the access points without any data
encryption or authentication.
Table 17 Network Setting > Wireless > General
LABEL DESCRIPTION
Wireless Network Setup
Band This shows the wireless band which this radio profile is using. 2.4GHz is the frequency used by IEEE
802.11b/g/n wireless clients.
Wireless You can Enable or Disable the wireless LAN in this field.
Channel Use Auto to have the VMG automatically determine a channel to use.
Bandwidth Select whether the VMG uses a wireless channel width of 20MHz or 40MHz.
A standard 20MHz channel offers transfer speeds of up to 150Mbps whereas a 40MHz channel
uses two standard channels and offers speeds of up to 300 Mbps.
40MHz (channel bonding or dual channel) bonds two adjacent radio channels to increase
throughput. The wireless clients must also support 40 MHz. It is often better to use the 20 MHz
setting in a location where the environment hinders the wireless signal.
Select 20MHz if you want to lessen radio interference with other wireless devices in your
neighborhood or the wireless clients do not support channel bonding.
Control
Sideband
This is available for some regions when you select a specific channel and set the Bandwidth field
to 40MHz. Set whether the control channel (set in the Channel field) should be in the Lower or
Upper range of channel bands.
Wireless Network Settings
Wireless
Network Name
The SSID (Service Set IDentity) identifies the service set with which a wireless device is associated.
Wireless devices associating to the access point (AP) must have the same SSID.
Enter a descriptive name (up to 32 English keyboard characters) for the wireless LAN.
Max Clients Specify the maximum number of clients that can connect to this network at the same time.
Hide SSID Select this check box to hide the SSID in the outgoing beacon frame so a station cannot obtain
the SSID through scanning using a site survey tool.
Multicast
Forwarding
Select this check box to allow the VMG to convert wireless multicast traffic into wireless unicast
traffic.
Max. Upstream
Bandwidth
Specify the maximum rate for upstream wireless traffic to the WAN from this WLAN in kilobits per
second (Kbps).
Max.
Downstream
Bandwidth
Specify the maximum rate for downstream wireless traffic to this WLAN from the WAN in kilobits
per second (Kbps).
BSSID This shows the MAC address of the wireless interface on the VMG when wireless LAN is enabled.
Security Level Select Basic (WEP) or More Secure (WPA-PSK, WPA2-PSK , WPA-WPA2-PSK) to add security on this
wireless network. The wireless clients which want to associate to this network must have same
wireless security settings as the VMG. When you select to use a security, additional options
appears in this screen.
Or you can select No Security to allow any client to associate this network without any data
encryption or authentication.
See the following sections for more details about this field.
Apply Click Apply to save your changes.
Cancel Click Cancel to restore your previously saved settings.
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Note: If you do not enable any wireless security on your VMG, your network is accessible to
any wireless networking device that is within range.
Figure 36 Wireless > General: No Security
The following table describes the labels in this screen.
7.2.2 Basic (WEP Encryption)
WEP encryption scrambles the data transmitted between the wireless stations and the access points
(AP) to keep network communications private. Both the wireless stations and the access points must use
the same WEP key.
Note: WEP is extremely insecure. Its encryption can be broken by an attacker, using widely-
available software. It is strongly recommended that you use a more effective security
mechanism. Use the strongest security mechanism that all the wireless devices in your
network support. For example, use WPA-PSK or WPA2-PSK if all your wireless devices
support it, or use WPA or WPA2 if your wireless devices support it and you have a RADIUS
server. If your wireless devices support nothing stronger than WEP, use the highest
encryption level available.
Your VMG allows you to configure up to four 64-bit or 128-bit WEP keys but only one key can be enabled
at any one time.
In order to configure and enable WEP encryption, click Network Setting > Wireless to display the General
screen, then select Basic as the security level.
Figure 37 Wireless > General: Basic (WEP)
Table 18 Wireless > General: No Security
LABEL DESCRIPTION
Security Level Choose No Security to allow all wireless connections without data encryption or authentication.
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The following table describes the labels in this screen.
7.2.3 More Secure (WPA(2)-PSK)
The WPA-PSK security mode provides both improved data encryption and user authentication over
WEP. Using a Pre-Shared Key (PSK), both the VMG and the connecting client share a common password
in order to validate the connection. This type of encryption, while robust, is not as strong as WPA, WPA2
or even WPA2-PSK. The WPA2-PSK security mode is a newer, more robust version of the WPA encryption
standard. It offers slightly better security, although the use of PSK makes it less robust than it could be.
Click Network Setting > Wireless to display the General screen. Select More Secure as the security level.
Note: WPA-PSK is not available if you enable WPS before you configure them.
Figure 38 Wireless > General: More Secure: WPA2-PSK
Table 19 Wireless > General: Basic (WEP)
LABEL DESCRIPTION
Security Level Select Basic to enable WEP data encryption.
Security Mode This shows WEP when you set Security Level to Basic.
Generate
password
automatically
Select this option to have the VMG automatically generate a password. The password field will
not be configurable when you select this option.
Password 1~4 The password (WEP keys) are used to encrypt data. Both the VMG and the wireless stations must
use the same password (WEP key) for data transmission.
If you chose 64-bit WEP, then enter any 5 ASCII characters or 10 hexadecimal characters ("0-9",
"A-F").
If you chose 128-bit WEP, then enter 13 ASCII characters or 26 hexadecimal characters ("0-9", "A-
F").
You must configure at least one password, only one password can be activated at any one
time.
Select password unmask to display the entered password in plain text. Clear it to hide the
password to avoid shoulder surfing.
more.../hide Click more... to show more fields in this section. Click hide to hide them.
WEP Encryption Select 64-bit or 128-bit.
This dictates the length of the security key that the network is going to use.
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The following table describes the labels in this screen.
7.3 The Guest/More AP Screen
This screen allows you to enable and configure multiple Basic Service Sets (BSSs) on the VMG.
Click Network Setting > Wireless > Guest/More AP. The following screen displays.
The following table introduces the supported wireless networks..
Figure 39 Network Setting > Wireless > Guest/More AP
Table 20 Wireless > General: More Secure: WPA2-PSK
LABEL DESCRIPTION
Security Level Select More Secure to enable WPA2-PSK data encryption.
Security Mode Select WPA-PSK, WPA2-PSK or WPA-WPA2-PSK from the drop-down list box.
Generate
password
automatically
Select this option to have the VMG automatically generate a password. The password field will
not be configurable when you select this option.
Password If you did not select Generate password automatically, you can manually type a pre-shared key
from 8 to 64 case-sensitive keyboard characters.
Select password unmask to display the entered password in plain text. Clear it to hide the
password to avoid shoulder surfing.
more.../hide Click more... to show more fields in this section. Click hide to hide them.
Encryption Select the encryption type (TKIP, AES or TKIP+AES) for data encryption.
Select TKIP if your wireless clients can all use TKIP.
Select AES if your wireless clients can all use AES.
Select TKIP+AES to allow the wireless clients to use either TKIP or AES.
Group Key
Update Timer
The Group Key Update Timer is the rate at which the RADIUS server sends a new group key out to
all clients.
Table 21 Supported Wireless Networks
WIRELESS
NETWORKS WHERE TO CONFIGURE
Main/1 Network Setting > Wireless >
General screen
Guest/3 Network Setting > Wireless >
Guest/More AP screen
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The following table describes the labels in this screen.
7.3.1 Edit Guest/More AP
Use this screen to edit an SSID profile. Click the Edit icon next to an SSID in the Guest/More AP screen. The
following screen displays.
Table 22 Network Setting > Wireless > Guest/More AP
LABEL DESCRIPTION
# This is the index number of the entry.
Status This field indicates whether this SSID is active. A yellow bulb signifies that this SSID is active. A gray
bulb signifies that this SSID is not active.
SSID An SSID profile is the set of parameters relating to one of the VMG’s BSSs. The SSID (Service Set
IDentifier) identifies the Service Set with which a wireless device is associated.
This field displays the name of the wireless profile on the network. When a wireless client scans for
an AP to associate with, this is the name that is broadcast and seen in the wireless client utility.
Security This field indicates the security mode of the SSID profile.
Guest WLAN This displays if the guest WLAN function has been enabled for this WLAN.
If Home Guest displays, clients connecting to the same SSID can communicate with each other
directly.
If External Guest displays, clients are blocked from connecting to each other directly.
N/A displays if guest WLAN is disabled.
Modify Click the Edit icon to configure the SSID profile.
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Figure 40 Network Setting > Wireless > Guest/More AP > Edit
The following table describes the fields in this screen.
Table 23 Network Setting > Wireless > Guest/More AP > Edit
LABEL DESCRIPTION
Wireless Network Setup
Wireless You can Enable or Disable the wireless LAN in this field.
Wireless Network Settings
Wireless
Network Name
The SSID (Service Set IDentity) identifies the service set with which a wireless device is associated.
Wireless devices associating to the access point (AP) must have the same SSID.
Enter a descriptive name (up to 32 English keyboard characters) for the wireless LAN.
Hide SSID Select this check box to hide the SSID in the outgoing beacon frame so a station cannot obtain
the SSID through scanning using a site survey tool.
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7.4 The MAC Authentication Screen
This screen allows you to configure the VMG to give exclusive access to specific devices (Allow) or
exclude specific devices from accessing the VMG (Deny). Every Ethernet device has a unique MAC
(Media Access Control) address. The MAC address is assigned at the factory and consists of six pairs of
hexadecimal characters, for example, 00:A0:C5:01:23:45. You need to know the MAC addresses of the
devices to configure this screen.
Use this screen to view your VMG’s MAC filter settings and add new MAC filter rules. Click Network
Setting > Wireless > MAC Authentication. The screen appears as shown.
Guest WLAN Select this to create Guest WLANs for home and external clients. Select the WLAN type in the
Access Scenario field.
Access Scenario If you select Home Guest, clients connecting to the same SSID can communicate with each
other directly.
If you select External Guest, clients are blocked from connecting to each other directly.
Move your mouse over the network icon next to the drop-down list box to view the
corresponding network topology.
Max. Upstream
Bandwidth
Specify the maximum rate for upstream wireless traffic to the WAN from this WLAN in kilobits per
second (Kbps).
Max.
Downstream
Bandwidth
Specify the maximum rate for downstream wireless traffic to this WLAN from the WAN in kilobits
per second (Kbps).
SSID Subnet Select Enable if you want the wireless network interface to assign DHCP IP addresses to the
associated wireless clients.
DHCP Start
Address Specify the first of the contiguous addresses in the DHCP IP address pool.
The VMG assigns IP addresses from this DHCP pool to wireless clients connecting to the SSID.
DHCP End
Address Specify the last of the contiguous addresses in the DHCP IP address pool.
SSID Subnet
Mask Specify the subnet mask of the VMG for the SSID subnet.
LAN IP
Address Specify the IP address of the VMG for the SSID subnet.
Security Level
Security Mode Select Basic (WEP) or More Secure (WPA-PSK, WPA2-PSK, WPA-WPA2-PSK) to add security on this
wireless network. The wireless clients which want to associate to this network must have same
wireless security settings as the VMG. After you select to use a security, additional options
appears in this screen.
Or you can select No Security to allow any client to associate this network without any data
encryption or authentication.
See Section 7.2.1 on page 98 for more details about this field.
OK Click OK to save your changes.
Cancel Click Cancel to exit this screen without saving.
Table 23 Network Setting > Wireless > Guest/More AP > Edit (continued)
LABEL DESCRIPTION
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Figure 41 Network Setting > Wireless > MAC Authentication
The following table describes the labels in this screen.
7.5 The WPS Screen
Use this screen to configure WiFi Protected Setup (WPS) on your VMG.
WPS allows you to quickly set up a wireless network with strong security, without having to configure
security settings manually. Set up each WPS connection between two devices. Both devices must
support WPS. See Section 7.9.8.3 on page 118 for more information about WPS.
Table 24 Network Setting > Wireless > Authentication
LABEL DESCRIPTION
General
SSID Select the SSID for which you want to configure MAC filter settings.
MAC Restrict
Mode
Define the filter action for the list of MAC addresses in the MAC address list.
Select Disable to turn off MAC filtering.
Select Deny to block access to the VMG. MAC addresses not listed will be allowed to access
the VMG.
Select Allow to permit access to the VMG. MAC addresses not listed will be denied access to
the VMG.
MAC address List
Add new MAC
address
Click this if you want to add a new MAC address entry to the MAC filter list below. This button is
not configurable when you select Disable in the MAC Restrict Mode field.
Enter the MAC addresses of the wireless devices that are allowed or denied access to the
VMG. Enter the MAC addresses in a valid MAC address format, that is, six hexadecimal
character pairs, for example, 12:34:56:78:9a:bc.
# This is the index number of the entry.
MAC Address This is the MAC addresses of the wireless devices that are allowed or denied access to the
VMG.
Modify Click the Edit icon to change the MAC address.
Click the Delete icon to remove the entry.
Apply Click Apply to save your changes.
Cancel Click Cancel to restore your previously saved settings.
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Note: The VMG applies the security settings of the SSID1 profile (see Section 7.2 on page 97). If
you want to use the WPS feature, make sure you have set the security mode of SSID1 to
WPA2-PSK or No Security.
Click Network Setting > Wireless > WPS. The following screen displays. Select Enable and click Apply to
activate the WPS function. Then you can configure the WPS settings in this screen.
Figure 42 Network Setting > Wireless > WPS
The following table describes the labels in this screen.
Table 25 Network Setting > Wireless > WPS
LABEL DESCRIPTION
General
WPS Select Enable to activate WPS on this VMG.
Add a new device with WPS Method
Method 1 Use this section to set up a WPS wireless network using Push Button Configuration (PBC). Select
Enable and click Apply to activate WPS method 1 on the VMG.
WPS Click this button to add another WPS-enabled wireless device (within wireless range of the
VMG) to your wireless network. This button may either be a physical button on the outside of
device, or a menu button similar to the WPS button on this screen.
Note: You must press the other wireless device’s WPS button within two minutes of
pressing this button.
Method 2 Use this section to set up a WPS wireless network by entering the PIN of the client into the VMG.
Select Enable and click Apply to activate WPS method 2 on the VMG.
Register Enter the PIN of the device that you are setting up a WPS connection with and click Register to
authenticate and add the wireless device to your wireless network.
You can find the PIN either on the outside of the device, or by checking the device’s settings.
Note: You must also activate WPS on that device within two minutes to have it
present its PIN to the VMG.
Method 3 Use this section to set up a WPS wireless network by entering the PIN of the VMG into the client.
Select Enable and click Apply to activate WPS method 3 on the VMG.
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7.6 The WMM Screen
Use this screen to enable Wi-Fi MultiMedia (WMM) and WMM Power Save in wireless networks for
multimedia applications.
Click Network Setting > Wireless > WMM. The following screen displays.
Figure 43 Network Setting > Wireless > WMM
The following table describes the labels in this screen.
Release
Configuration The default WPS status is configured.
Click this button to remove all configured wireless and wireless security settings for WPS
connections on the VMG.
Generate
New PIN
Number
If this method has been enabled, the PIN (Personal Identification Number) of the VMG is shown
here. Enter this PIN in the configuration utility of the device you want to connect to using WPS.
The PIN is not necessary when you use WPS push-button method.
Click the Generate New PIN button to have the VMG create a new PIN.
Apply Click Apply to save your changes.
Cancel Click Cancel to restore your previously saved settings.
Table 25 Network Setting > Wireless > WPS (continued)
LABEL DESCRIPTION
Table 26 Network Setting > Wireless > WMM
LABEL DESCRIPTION
WMM of SSID1~4 Select On to have the VMG automatically give the wireless network (SSIDx) a priority level
according to the ToS value in the IP header of packets it sends. WMM QoS (Wifi MultiMedia
Quality of Service) gives high priority to voice and video, which makes them run more smoothly.
WMM
Automatic
Power Save
Delivery(APSD)
Select this option to extend the battery life of your mobile devices (especially useful for small
devices that are running multimedia applications). The VMG goes to sleep mode to save power
when it is not transmitting data. The AP buffers the packets sent to the VMG until the VMG
"wakes up". The VMG wakes up periodically to check for incoming data.
Note: This works only if the wireless device to which the VMG is connected also
supports this feature.
Apply Click Apply to save your changes.
Cancel Click Cancel to restore your previously saved settings.
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7.7 The Others Screen
Use this screen to configure advanced wireless settings. Click Network Setting > Wireless > Others. The
screen appears as shown.
See Section 7.9.2 on page 112 for detailed definitions of the terms listed in this screen.
Figure 44 Network Setting > Wireless > Others
The following table describes the labels in this screen.
Table 27 Network Setting > Wireless > Others
LABEL DESCRIPTION
RTS/CTS
Threshold
Data with its frame size larger than this value will perform the RTS (Request To Send)/CTS (Clear
To Send) handshake.
Enter a value between 0 and 2347.
Fragmentation
Threshold
This is the maximum data fragment size that can be sent. Enter a value between 256 and 2346.
Output Power Set the output power of the VMG. If there is a high density of APs in an area, decrease the
output power to reduce interference with other APs. Select one of the following: 20%, 40%, 60%,
80% or 100%.
Beacon Interval When a wirelessly networked device sends a beacon, it includes with it a beacon interval. This
specifies the time period before the device sends the beacon again.
The interval tells receiving devices on the network how long they can wait in low power mode
before waking up to handle the beacon. This value can be set from 50ms to 1000ms. A high
value helps save current consumption of the access point.
DTIM Interval Delivery Traffic Indication Message (DTIM) is the time period after which broadcast and
multicast packets are transmitted to mobile clients in the Power Saving mode. A high DTIM
value can cause clients to lose connectivity with the network. This value can be set from 1 to
255.
802.11 Mode Select 802.11b Only to allow only IEEE 802.11b compliant WLAN devices to associate with the
VMG.
Select 802.11g Only to allow only IEEE 802.11g compliant WLAN devices to associate with the
VMG.
Select 802.11n Only to allow only IEEE 802.11n compliant WLAN devices to associate with the
VMG.
Select 802. 11 b /g M ixed to allow either IEEE 802.11b or IEEE 802.11g compliant WLAN devices to
associate with the VMG. The transmission rate of your VMG might be reduced.
Select 802.11b/g/n Mixed to allow IEEE 802.11b, IEEE 802.11g or IEEE802.11n compliant WLAN
devices to associate with the VMG. The transmission rate of your VMG might be reduced.
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7.8 The Channel Status Screen
Use the Channel Status screen to scan wireless LAN channel noises and view the results. Click Network
Setting > Wireless > Channel Status. The screen appears as shown. Click Scan to scan the wireless LAN
channels. You can view the results in the Channel Scan Result section.
Note: The Scan button only works when the VMG uses 20MHz for the wireless channel width.
You can go to the Network Setting > Wireless > General screen, click the more link, and
then change the channel width setting in the Bandwidth field.
802.11 Protection Enabling this feature can help prevent collisions in mixed-mode networks (networks with both
IEEE 802.11b and IEEE 802.11g traffic).
Select Auto to have the wireless devices transmit data after a RTS/CTS handshake. This helps
improve IEEE 802.11g performance.
Select Off to disable 802.11 protection. The transmission rate of your VMG might be reduced in a
mixed-mode network.
This field displays Off and is not configurable when you set 802.11 Mode to 802.11b Only.
Preamble Select a preamble type from the drop-down list box. Choices are Long or Short. See Section
7.9.7 on page 116 for more information.
This field is configurable only when you set 802.11 Mode to 802.11b.
OBSS
Coexistence
Select Enable to allow the coexistence of 20 MHz and 40 MHz Overlapping Basic Service Sets
(OBSS) in wireless local area networks. Select Disabled to disable this feature.
Apply Click Apply to save your changes.
Cancel Click Cancel to restore your previously saved settings.
Table 27 Network Setting > Wireless > Others (continued)
LABEL DESCRIPTION
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Figure 45 Network Setting > Wireless > Channel Status
7.9 Technical Reference
This section discusses wireless LANs in depth. For more information, see Appendix B on page 266.
7.9.1 Wireless Network Overview
Wireless networks consist of wireless clients, access points and bridges.
• A wireless client is a radio connected to a user’s computer.
• An access point is a radio with a wired connection to a network, which can connect with numerous
wireless clients and let them access the network.
• A bridge is a radio that relays communications between access points and wireless clients, extending
a network’s range.
Traditionally, a wireless network operates in one of two ways.
• An “infrastructure” type of network has one or more access points and one or more wireless clients.
The wireless clients connect to the access points.
• An “ad-hoc” type of network is one in which there is no access point. Wireless clients connect to one
another in order to exchange information.
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The following figure provides an example of a wireless network.
Figure 46 Example of a Wireless Network
The wireless network is the part in the blue circle. In this wireless network, devices A and B use the access
point (AP) to interact with the other devices (such as the printer) or with the Internet. Your VMG is the AP.
Every wireless network must follow these basic guidelines.
• Every device in the same wireless network must use the same SSID.
The SSID is the name of the wireless network. It stands for Service Set IDentifier.
• If two wireless networks overlap, they should use a different channel.
Like radio stations or television channels, each wireless network uses a specific channel, or frequency,
to send and receive information.
• Every device in the same wireless network must use security compatible with the AP.
Security stops unauthorized devices from using the wireless network. It can also protect the
information that is sent in the wireless network.
Radio Channels
In the radio spectrum, there are certain frequency bands allocated for unlicensed, civilian use. For the
purposes of wireless networking, these bands are divided into numerous channels. This allows a variety of
networks to exist in the same place without interfering with one another. When you create a network,
you must select a channel to use.
Since the available unlicensed spectrum varies from one country to another, the number of available
channels also varies.
DSL
AB
AP
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7.9.2 Additional Wireless Terms
The following table describes some wireless network terms and acronyms used in the VMG’s Web
Configurator.
7.9.3 Wireless Security Overview
By their nature, radio communications are simple to intercept. For wireless data networks, this means
that anyone within range of a wireless network without security can not only read the data passing over
the airwaves, but also join the network. Once an unauthorized person has access to the network, he or
she can steal information or introduce malware (malicious software) intended to compromise the
network. For these reasons, a variety of security systems have been developed to ensure that only
authorized people can use a wireless data network, or understand the data carried on it.
These security standards do two things. First, they authenticate. This means that only people presenting
the right credentials (often a username and password, or a “key” phrase) can access the network.
Second, they encrypt. This means that the information sent over the air is encoded. Only people with
the code key can understand the information, and only people who have been authenticated are
given the code key.
These security standards vary in effectiveness. Some can be broken, such as the old Wired Equivalent
Protocol (WEP). Using WEP is better than using no security at all, but it will not keep a determined
attacker out. Other security standards are secure in themselves but can be broken if a user does not use
them properly. For example, the WPA-PSK security standard is very secure if you use a long key which is
difficult for an attacker’s software to guess - for example, a twenty-letter long string of apparently
random numbers and letters - but it is not very secure if you use a short key which is very easy to guess -
for example, a three-letter word from the dictionary.
Because of the damage that can be done by a malicious attacker, it’s not just people who have
sensitive information on their network who should use security. Everybody who uses any wireless network
should ensure that effective security is in place.
A good way to come up with effective security keys, passwords and so on is to use obscure information
that you personally will easily remember, and to enter it in a way that appears random and does not
include real words. For example, if your mother owns a 1970 Dodge Challenger and her favorite movie is
Table 28 Additional Wireless Terms
TERM DESCRIPTION
RTS/CTS Threshold In a wireless network which covers a large area, wireless devices are sometimes not
aware of each other’s presence. This may cause them to send information to the AP at
the same time and result in information colliding and not getting through.
By setting this value lower than the default value, the wireless devices must sometimes get
permission to send information to the VMG. The lower the value, the more often the
devices must get permission.
If this value is greater than the fragmentation threshold value (see below), then wireless
devices never have to get permission to send information to the VMG.
Preamble A preamble affects the timing in your wireless network. There are two preamble modes:
long and short. If a device uses a different preamble mode than the VMG does, it cannot
communicate with the VMG.
Authentication The process of verifying whether a wireless device is allowed to use the wireless network.
Fragmentation
Threshold
A small fragmentation threshold is recommended for busy networks, while a larger
threshold provides faster performance if the network is not very busy.
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Vanishing Point (which you know was made in 1971) you could use “70dodchal71vanpoi” as your
security key.
The following sections introduce different types of wireless security you can set up in the wireless
network.
7.9.3.1 SSID
Normally, the VMG acts like a beacon and regularly broadcasts the SSID in the area. You can hide the
SSID instead, in which case the VMG does not broadcast the SSID. In addition, you should change the
default SSID to something that is difficult to guess.
This type of security is fairly weak, however, because there are ways for unauthorized wireless devices to
get the SSID. In addition, unauthorized wireless devices can still see the information that is sent in the
wireless network.
7.9.3.2 MAC Address Filter
Every device that can use a wireless network has a unique identification number, called a MAC
address.1 A MAC address is usually written using twelve hexadecimal characters2; for example,
00A0C5000002 or 00:A0:C5:00:00:02. To get the MAC address for each device in the wireless network,
see the device’s User’s Guide or other documentation.
You can use the MAC address filter to tell the VMG which devices are allowed or not allowed to use the
wireless network. If a device is allowed to use the wireless network, it still has to have the correct
information (SSID, channel, and security). If a device is not allowed to use the wireless network, it does
not matter if it has the correct information.
This type of security does not protect the information that is sent in the wireless network. Furthermore,
there are ways for unauthorized wireless devices to get the MAC address of an authorized device. Then,
they can use that MAC address to use the wireless network.
7.9.3.3 User Authentication
Authentication is the process of verifying whether a wireless device is allowed to use the wireless
network. You can make every user log in to the wireless network before using it. However, every device
in the wireless network has to support IEEE 802.1x to do this.
For wireless networks, you can store the user names and passwords for each user in a RADIUS server. This
is a server used in businesses more than in homes. If you do not have a RADIUS server, you cannot set up
user names and passwords for your users.
Unauthorized wireless devices can still see the information that is sent in the wireless network, even if they
cannot use the wireless network. Furthermore, there are ways for unauthorized wireless users to get a
valid user name and password. Then, they can use that user name and password to use the wireless
network.
1. Some wireless devices, such as scanners, can detect wireless networks but cannot use wireless networks. These
kinds of wireless devices might not have MAC addresses.
2. Hexadecimal characters are 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, and F.
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7.9.3.4 Encryption
Wireless networks can use encryption to protect the information that is sent in the wireless network.
Encryption is like a secret code. If you do not know the secret code, you cannot understand the
message.
The types of encryption you can choose depend on the type of authentication. (See Section 7.9.3.3 on
page 113 for information about this.)
For example, if the wireless network has a RADIUS server, you can choose WPA or WPA2. If users do not
log in to the wireless network, you can choose no encryption, Static WEP, WPA-PSK, or WPA2-PSK.
Usually, you should set up the strongest encryption that every device in the wireless network supports. For
example, suppose you have a wireless network with the VMG and you do not have a RADIUS server.
Therefore, there is no authentication. Suppose the wireless network has two devices. Device A only
supports WEP, and device B supports WEP and WPA. Therefore, you should set up Static WEP in the
wireless network.
Note: It is recommended that wireless networks use WPA-PSK, WPA, or stronger encryption.
The other types of encryption are better than none at all, but it is still possible for
unauthorized wireless devices to figure out the original information pretty quickly.
When you select WPA2 or WPA2-PSK in your VMG, you can also select an option (WPA compatible) to
support WPA as well. In this case, if some of the devices support WPA and some support WPA2, you
should set up WPA2-PSK or WPA2 (depending on the type of wireless network login) and select the WPA
compatible option in the VMG.
Many types of encryption use a key to protect the information in the wireless network. The longer the
key, the stronger the encryption. Every device in the wireless network must have the same key.
7.9.4 Signal Problems
Because wireless networks are radio networks, their signals are subject to limitations of distance,
interference and absorption.
Problems with distance occur when the two radios are too far apart. Problems with interference occur
when other radio waves interrupt the data signal. Interference may come from other radio
transmissions, such as military or air traffic control communications, or from machines that are
coincidental emitters such as electric motors or microwaves. Problems with absorption occur when
physical objects (such as thick walls) are between the two radios, muffling the signal.
Table 29 Types of Encryption for Each Type of Authentication
NO AUTHENTICATION RADIUS SERVER
Weakest No Security WPA
Static WEP
WPA-PSK
Strongest WPA2-PSK WPA2
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7.9.5 BSS
A Basic Service Set (BSS) exists when all communications between wireless stations or between a wireless
station and a wired network client go through one access point (AP).
Intra-BSS traffic is traffic between wireless stations in the BSS. When Intra-BSS traffic blocking is disabled,
wireless station A and B can access the wired network and communicate with each other. When Intra-
BSS traffic blocking is enabled, wireless station A and B can still access the wired network but cannot
communicate with each other.
Figure 47 Basic Service Set
7.9.6 MBSSID
Traditionally, you need to use different APs to configure different Basic Service Sets (BSSs). As well as the
cost of buying extra APs, there is also the possibility of channel interference. The VMG’s MBSSID (Multiple
Basic Service Set IDentifier) function allows you to use one access point to provide several BSSs
simultaneously. You can then assign varying QoS priorities and/or security modes to different SSIDs.
Wireless devices can use different BSSIDs to associate with the same AP.
7.9.6.1 Notes on Multiple BSSs
• A maximum of eight BSSs are allowed on one AP simultaneously.
• You must use different keys for different BSSs. If two wireless devices have different BSSIDs (they are in
different BSSs), but have the same keys, they may hear each other’s communications (but not
communicate with each other).
• MBSSID should not replace but rather be used in conjunction with 802.1x security.
DSL
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7.9.7 Preamble Type
Preamble is used to signal that data is coming to the receiver. Short and long refer to the length of the
synchronization field in a packet.
Short preamble increases performance as less time sending preamble means more time for sending
data. All IEEE 802.11 compliant wireless adapters support long preamble, but not all support short
preamble.
Use long preamble if you are unsure what preamble mode other wireless devices on the network
support, and to provide more reliable communications in busy wireless networks.
Use short preamble if you are sure all wireless devices on the network support it, and to provide more
efficient communications.
Use the dynamic setting to automatically use short preamble when all wireless devices on the network
support it, otherwise the VMG uses long preamble.
Note: The wireless devices MUST use the same preamble mode in order to communicate.
7.9.8 WiFi Protected Setup (WPS)
Your VMG supports WiFi Protected Setup (WPS), which is an easy way to set up a secure wireless
network. WPS is an industry standard specification, defined by the WiFi Alliance.
WPS allows you to quickly set up a wireless network with strong security, without having to configure
security settings manually. Each WPS connection works between two devices. Both devices must
support WPS (check each device’s documentation to make sure).
Depending on the devices you have, you can either press a button (on the device itself, or in its
configuration utility) or enter a PIN (a unique Personal Identification Number that allows one device to
authenticate the other) in each of the two devices. When WPS is activated on a device, it has two
minutes to find another device that also has WPS activated. Then, the two devices connect and set up
a secure network by themselves.
7.9.8.1 Push Button Configuration
WPS Push Button Configuration (PBC) is initiated by pressing a button on each WPS-enabled device, and
allowing them to connect automatically. You do not need to enter any information.
Not every WPS-enabled device has a physical WPS button. Some may have a WPS PBC button in their
configuration utilities instead of or in addition to the physical button.
Take the following steps to set up WPS using the button.
1Ensure that the two devices you want to set up are within wireless range of one another.
2Look for a WPS button on each device. If the device does not have one, log into its configuration utility
and locate the button (see the device’s User’s Guide for how to do this - for the VMG, see Section 7.6 on
page 107).
3Press the button on one of the devices (it doesn’t matter which). For the VMG you must press the WPS
button for more than five seconds.
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4Within two minutes, press the button on the other device. The registrar sends the network name (SSID)
and security key through an secure connection to the enrollee.
If you need to make sure that WPS worked, check the list of associated wireless clients in the AP’s
configuration utility. If you see the wireless client in the list, WPS was successful.
7.9.8.2 PIN Configuration
Each WPS-enabled device has its own PIN (Personal Identification Number). This may either be static (it
cannot be changed) or dynamic (in some devices you can generate a new PIN by clicking on a button
in the configuration interface).
Use the PIN method instead of the push-button configuration (PBC) method if you want to ensure that
the connection is established between the devices you specify, not just the first two devices to activate
WPS in range of each other. However, you need to log into the configuration interfaces of both devices
to use the PIN method.
When you use the PIN method, you must enter the PIN from one device (usually the wireless client) into
the second device (usually the Access Point or wireless router). Then, when WPS is activated on the first
device, it presents its PIN to the second device. If the PIN matches, one device sends the network and
security information to the other, allowing it to join the network.
Take the following steps to set up a WPS connection between an access point or wireless router
(referred to here as the AP) and a client device using the PIN method.
1Ensure WPS is enabled on both devices.
2Access the WPS section of the AP’s configuration interface. See the device’s User’s Guide for how to do
this.
3Look for the client’s WPS PIN; it will be displayed either on the device, or in the WPS section of the client’s
configuration interface (see the device’s User’s Guide for how to find the WPS PIN - for the VMG, see
Section 7.5 on page 105).
4Enter the client’s PIN in the AP’s configuration interface.
5If the client device’s configuration interface has an area for entering another device’s PIN, you can
either enter the client’s PIN in the AP, or enter the AP’s PIN in the client - it does not matter which.
6Start WPS on both devices within two minutes.
7Use the configuration utility to activate WPS, not the push-button on the device itself.
8On a computer connected to the wireless client, try to connect to the Internet. If you can connect, WPS
was successful.
If you cannot connect, check the list of associated wireless clients in the AP’s configuration utility. If you
see the wireless client in the list, WPS was successful.
The following figure shows a WPS-enabled wireless client (installed in a notebook computer) connecting
to the WPS-enabled AP via the PIN method.
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Figure 48 Example WPS Process: PIN Method
7.9.8.3 How WPS Works
When two WPS-enabled devices connect, each device must assume a specific role. One device acts
as the registrar (the device that supplies network and security settings) and the other device acts as the
enrollee (the device that receives network and security settings. The registrar creates a secure EAP
(Extensible Authentication Protocol) tunnel and sends the network name (SSID) and the WPA-PSK or
WPA2-PSK pre-shared key to the enrollee. Whether WPA-PSK or WPA2-PSK is used depends on the
standards supported by the devices. If the registrar is already part of a network, it sends the existing
information. If not, it generates the SSID and WPA(2)-PSK randomly.
The following figure shows a WPS-enabled client (installed in a notebook computer) connecting to a
WPS-enabled access point.
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Figure 49 How WPS works
The roles of registrar and enrollee last only as long as the WPS setup process is active (two minutes). The
next time you use WPS, a different device can be the registrar if necessary.
The WPS connection process is like a handshake; only two devices participate in each WPS transaction.
If you want to add more devices you should repeat the process with one of the existing networked
devices and the new device.
Note that the access point (AP) is not always the registrar, and the wireless client is not always the
enrollee. All WPS-certified APs can be a registrar, and so can some WPS-enabled wireless clients.
By default, a WPS devices is “unconfigured”. This means that it is not part of an existing network and can
act as either enrollee or registrar (if it supports both functions). If the registrar is unconfigured, the security
settings it transmits to the enrollee are randomly-generated. Once a WPS-enabled device has
connected to another device using WPS, it becomes “configured”. A configured wireless client can still
act as enrollee or registrar in subsequent WPS connections, but a configured access point can no longer
act as enrollee. It will be the registrar in all subsequent WPS connections in which it is involved. If you
want a configured AP to act as an enrollee, you must reset it to its factory defaults.
7.9.8.4 Example WPS Network Setup
This section shows how security settings are distributed in an example WPS setup.
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The following figure shows an example network. In step 1, both AP1 and Client 1 are unconfigured.
When WPS is activated on both, they perform the handshake. In this example, AP1 is the registrar, and
Client 1 is the enrollee. The registrar randomly generates the security information to set up the network,
since it is unconfigured and has no existing information.
Figure 50 WPS: Example Network Step 1
In step 2, you add another wireless client to the network. You know that Client 1 supports registrar mode,
but it is better to use AP1 for the WPS handshake with the new client since you must connect to the
access point anyway in order to use the network. In this case, AP1 must be the registrar, since it is
configured (it already has security information for the network). AP1 supplies the existing security
information to Client 2.
Figure 51 WPS: Example Network Step 2
In step 3, you add another access point (AP2) to your network. AP2 is out of range of AP1, so you cannot
use AP1 for the WPS handshake with the new access point. However, you know that Client 2 supports
the registrar function, so you use it to perform the WPS handshake instead.
DSL
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Figure 52 WPS: Example Network Step 3
7.9.8.5 Limitations of WPS
WPS has some limitations of which you should be aware.
• WPS works in Infrastructure networks only (where an AP and a wireless client communicate). It does
not work in Ad-Hoc networks (where there is no AP).
• When you use WPS, it works between two devices only. You cannot enroll multiple devices
simultaneously, you must enroll one after the other.
For instance, if you have two enrollees and one registrar you must set up the first enrollee (by pressing
the WPS button on the registrar and the first enrollee, for example), then check that it successfully
enrolled, then set up the second device in the same way.
• WPS works only with other WPS-enabled devices. However, you can still add non-WPS devices to a
network you already set up using WPS.
WPS works by automatically issuing a randomly-generated WPA-PSK or WPA2-PSK pre-shared key
from the registrar device to the enrollee devices. Whether the network uses WPA-PSK or WPA2-PSK
depends on the device. You can check the configuration interface of the registrar device to discover
the key the network is using (if the device supports this feature). Then, you can enter the key into the
non-WPS device and join the network as normal (the non-WPS device must also support WPA-PSK or
WPA2-PSK).
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• When you use the PBC method, there is a short period (from the moment you press the button on one
device to the moment you press the button on the other device) when any WPS-enabled device
could join the network. This is because the registrar has no way of identifying the “correct” enrollee,
and cannot differentiate between your enrollee and a rogue device. This is a possible way for a
hacker to gain access to a network.
You can easily check to see if this has happened. WPS works between only two devices
simultaneously, so if another device has enrolled your device will be unable to enroll, and will not
have access to the network. If this happens, open the access point’s configuration interface and look
at the list of associated clients (usually displayed by MAC address). It does not matter if the access
point is the WPS registrar, the enrollee, or was not involved in the WPS handshake; a rogue device
must still associate with the access point to gain access to the network. Check the MAC addresses of
your wireless clients (usually printed on a label on the bottom of the device). If there is an unknown
MAC address you can remove it or reset the AP.
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CHAPTER 8
Home Networking
8.1 Overview
A Local Area Network (LAN) is a shared communication system to which many networking devices are
connected. It is usually located in one immediate area such as a building or floor of a building.
Use the LAN screens to help you configure a LAN DHCP server and manage IP addresses.
8.1.1 What You Can Do in this Chapter
• Use the LAN Setup screen to set the LAN IP address, subnet mask, and DHCP settings of your VMG
(Section 8.2 on page 125).
• Use the Static DHCP screen to assign IP addresses on the LAN to specific individual computers based
on their MAC Addresses (Section 8.3 on page 129).
• Use the UPnP screen to enable UPnP and UPnP NAT traversal on the VMG (Section 8.4 on page 130).
• Use the Additional Subnet screen to configure IP alias and public static IP (Section 8.5 on page 133).
• Use the STB Vendor ID screen to configure the Vendor IDs of the connected Set Top Box (STB) devices,
which have the VMG automatically create static DHCP entries for the STB devices when they request
IP addresses (Section 8.6 on page 134).
• Use the Wake on LAN screen to remotely turn on a device on the network. (Section 8.7 on page 134).
• Use the TFTP Server Name screen to set a TFTP server address which is passed to the clients using DHCP
option 66. (Section 8.8 on page 135).
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8.1.2 What You Need To Know
8.1.2.1 About LAN
IP Address
IP addresses identify individual devices on a network. Every networking device (including computers,
servers, routers, printers, etc.) needs an IP address to communicate across the network. These
networking devices are also known as hosts.
Subnet Mask
Subnet masks determine the maximum number of possible hosts on a network. You can also use subnet
masks to divide one network into multiple sub-networks.
DHCP
A DHCP (Dynamic Host Configuration Protocol) server can assign your VMG an IP address, subnet mask,
DNS and other routing information when it's turned on.
DNS
DNS (Domain Name System) is for mapping a domain name to its corresponding IP address and vice
versa. The DNS server is extremely important because without it, you must know the IP address of a
networking device before you can access it.
RADVD (Router Advertisement Daemon)
When an IPv6 host sends a Router Solicitation (RS) request to discover the available routers, RADVD with
Router Advertisement (RA) messages in response to the request. It specifies the minimum and maximum
intervals of RA broadcasts. RA messages containing the address prefix. IPv6 hosts can be generated
with the IPv6 prefix an IPv6 address.
8.1.2.2 About UPnP
Identifying UPnP Devices
UPnP hardware is identified as an icon in the Network Connections folder (Windows XP). Each UPnP
compatible device installed on your network will appear as a separate icon. Selecting the icon of a
UPnP device will allow you to access the information and properties of that device.
NAT Traversal
UPnP NAT traversal automates the process of allowing an application to operate through NAT. UPnP
network devices can automatically configure network addressing, announce their presence in the
network to other UPnP devices and enable exchange of simple product and service descriptions. NAT
traversal allows the following:
• Dynamic port mapping
• Learning public IP addresses
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• Assigning lease times to mappings
Windows Messenger is an example of an application that supports NAT traversal and UPnP.
See the Chapter 11 on page 163 for more information on NAT.
Cautions with UPnP
The automated nature of NAT traversal applications in establishing their own services and opening
firewall ports may present network security issues. Network information and configuration may also be
obtained and modified by users in some network environments.
When a UPnP device joins a network, it announces its presence with a multicast message. For security
reasons, the VMG allows multicast messages on the LAN only.
All UPnP-enabled devices may communicate freely with each other without additional configuration.
Disable UPnP if this is not your intention.
UPnP and Zyxel
Zyxel has achieved UPnP certification from the Universal Plug and Play Forum UPnP™ Implementers
Corp. (UIC). Zyxel's UPnP implementation supports Internet Gateway Device (IGD) 1.0.
See Section 8.4.1 on page 131 for examples of installing and using UPnP.
Finding Out More
See Section 8.9 on page 135 for technical background information on LANs.
8.1.3 Before You Begin
Find out the MAC addresses of your network devices if you intend to add them to the DHCP Client List
screen.
8.2 The LAN Setup Screen
Use this screen to set the Local Area Network IP address and subnet mask of your VMG. Click Network
Setting > Home Networking to open the LAN Setup screen.
Follow these steps to configure your LAN settings.
1Enter an IP address into the IP Address field. The IP address must be in dotted decimal notation. This will
become the IP address of your VMG.
2Enter the IP subnet mask into the IP Subnet Mask field. Unless instructed otherwise it is best to leave this
alone, the configurator will automatically compute a subnet mask based upon the IP address you
entered.
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3Click Apply to save your settings.
Figure 53 Network Setting > Home Networking > LAN Setup
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The following table describes the fields in this screen.
Table 30 Network Setting > Home Networking > LAN Setup
LABEL DESCRIPTION
Interface Group
Group Name Select the interface group name for which you want to configure LAN settings. See Chapter 13
on page 183 for how to create a new interface group.
LAN IP Setup
IP Address Enter the LAN IPv4 address you want to assign to your VMG in dotted decimal notation, for
example, 192.168.1.1 (factory default).
Subnet Mask Type the subnet mask of your network in dotted decimal notation, for example 255.255.255.0
(factory default).
DHCP Server State
DHCP Select Enable to have the VMG act as a DHCP server or DHCP relay agent.
Select Disable to stop the DHCP server on the VMG.
Select DHCP Relay to have the VMG forward DHCP request to the DHCP server.
DHCP Relay
Server Address
This field is only available when you select DHCP Relay in the DHCP field.
IP Address Enter the IPv4 address of the actual remote DHCP server in this field.
IP Addressing
Values
This field is only available when you select Enable in the DHCP field.
Beginning IP
Address
This field specifies the first of the contiguous addresses in the IP address pool.
Ending IP
Address
This field specifies the last of the contiguous addresses in the IP address pool.
Auto reserve IP
for the same
host
Select Enable to have the VMG record DHCP IP addresses with the MAC addresses the IP
addresses are assigned to. The VMG assigns the same IP address to the same MAC address
when the host requests an IP address again through DHCP.
DHCP Server
Lease Time
This is the period of time DHCP-assigned addresses is used. DHCP automatically assigns IP
addresses to clients when they log in. DHCP centralizes IP address management on central
computers that run the DHCP server program. DHCP leases addresses, for a period of time,
which means that past addresses are “recycled” and made available for future reassignment to
other systems.
This field is only available when you select Enable in the DHCP field.
Days/Hours/
Minutes
Enter the lease time of the DHCP server.
DNS Values This field is only available when you select Enable in the DHCP field.
DNS Select From ISP if your ISP dynamically assigns DNS server information.
Select DNS Proxy if you have the DNS proxy service. The VMG redirects clients’ DNS queries to a
DNS server for resolving domain names.
Select Static if you have the IP address of a DNS server.
DNS Server 1/2 Enter the first and second DNS (Domain Name System) server IP addresses the VMG passes to
the DHCP clients.
LAN IPv6 Mode Setup
IPv6 Active Select Enable to activate the IPv6 mode and configure IPv6 settings on the VMG.
Link Local Address Type
EUI64 Select this to have the VMG generate an interface ID for the LAN interface’s link-local address
using the EUI-64 format.
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Manual Select this to manually enter an interface ID for the LAN interface’s link-local address.
LAN Global Identifier Type
EUI64 Select this to have the VMG generate an interface ID using the EUI-64 format for its global
address.
Manual Select this to manually enter an interface ID for the LAN interface’s global IPv6 address.
LAN IPv6 Address Setup
Delegate prefix
from WAN
Select this option to automatically obtain an IPv6 network prefix from the service provider or an
uplink router.
Static Select this option to configure a fixed IPv6 address for the VMG’s LAN IPv6 address.
LAN IPv6
Address Assign
Setup
Select how you want to obtain an IPv6 address:
•Stateless: The VMG uses IPv6 stateless autoconfiguration. RADVD (Router Advertisement
Daemon) is enabled to have the VMG send IPv6 prefix information in router advertisements
periodically and in response to router solicitations. DHCPv6 server is disabled.
•Stateful: The VMG uses IPv6 stateful autoconfiguration. The DHCPv6 server is enabled to have
the VMG act as a DHCPv6 server and pass IPv6 addresses to DHCPv6 clients.
LAN IPv6 DNS
Assign Setup
Select how the VMG provide DNS server and domain name information to the clients:
•From Router Advertisement: The VMG provides DNS information through router
advertisements.
•From DHCPv6 Server: The VMG provides DNS information through DHCPv6.
•From RA & DHCPv6 Server: The VMG provides DNS information through both router
advertisements and DHCPv6.
DHCPv6 Configuration
DHCPv6 Active This shows the status of the DHCPv6. DHCPv6 Serve r displays if you configured the VMG to act as
a DHCPv6 server which assigns IPv6 addresses and/or DNS information to clients.
IPv6 Router Advertisement State
RADVD Active This shows whether RADVD is enabled or not.
IPv6 DNS Values
IPv6 DNS Server
1-3
Select From ISP if your ISP dynamically assigns IPv6 DNS server information.
Select User-Defined if you have the IPv6 address of a DNS server. Enter the DNS server IPv6
addresses the VMG passes to the DHCP clients.
Select None if you do not want to configure IPv6 DNS servers.
DNS Query
Scenario
Select how the VMG handles clients’ DNS information requests.
•IPv4/IPv6 DNS Server: The VMG forwards the requests to both the IPv4 and IPv6 DNS servers
and sends clients the first DNS information it receives.
•IPv6 DNS Server Only: The VMG forwards the requests to the IPv6 DNS server and sends clients
the DNS information it receives.
•IPv4 DNS Server Only: The VMG forwards the requests to the IPv4 DNS server and sends clients
the DNS information it receives.
•IPv6 DNS Server First: The VMG forwards the requests to the IPv6 DNS server first and then the
IPv4 DNS server. Then it sends clients the first DNS information it receives.
•IPv4 DNS Server First: The VMG forwards the requests to the IPv4 DNS server first and then the
IPv6 DNS server. Then it sends clients the first DNS information it receives.
Apply Click Apply to save your changes.
Cancel Click Cancel to restore your previously saved settings.
Table 30 Network Setting > Home Networking > LAN Setup (continued)
LABEL DESCRIPTION
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8.3 The Static DHCP Screen
This table allows you to assign IP addresses on the LAN to specific individual computers based on their
MAC Addresses.
Every Ethernet device has a unique MAC (Media Access Control) address. The MAC address is assigned
at the factory and consists of six pairs of hexadecimal characters, for example, 00:A0:C5:00:00:02.
Use this screen to change your VMG’s static DHCP settings. Click Network Setting > Home Networking >
Static DHCP to open the following screen.
Figure 54 Network Setting > Home Networking > Static DHCP
The following table describes the labels in this screen.
If you click Static DHCP Configuration in the Static DHCP screen or the Edit icon next to a static DHCP
entry, the following screen displays.
Table 31 Network Setting > Home Networking > Static DHCP
LABEL DESCRIPTION
Static DHCP
Configuration
Click this to add a new static DHCP entry.
# This is the index number of the entry.
Status This field displays whether the client is connected to the VMG.
MAC Address The MAC (Media Access Control) or Ethernet address on a LAN (Local Area Network) is
unique to your computer (six pairs of hexadecimal notation).
A network interface card such as an Ethernet adapter has a hardwired address that is
assigned at the factory. This address follows an industry standard that ensures no other
adapter has a similar address.
IP Address This field displays the IP address relative to the # field listed above.
Modify Click the Edit icon to have the IP address field editable and change it.
Click the Delete icon to delete a static DHCP entry. A window displays asking you to confirm
that you want to delete the selected entry.
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Figure 55 Static DHCP: Static DHCP Configuration/Edit
The following table describes the labels in this screen.
8.4 The UPnP Screen
Universal Plug and Play (UPnP) is a distributed, open networking standard that uses TCP/IP for simple
peer-to-peer network connectivity between devices. A UPnP device can dynamically join a network,
obtain an IP address, convey its capabilities and learn about other devices on the network. In turn, a
device can leave a network smoothly and automatically when it is no longer in use.
See page 124 for more information on UPnP.
Table 32 Static DHCP: Static DHCP Configuration/Edit
LABEL DESCRIPTION
Active Select Enable to activate the connection between the client and the VMG. Otherwise, select
Disable to deactivate.
Group Name Select the interface group name for which you want to configure static DHCP settings. See
Chapter 13 on page 183 for how to create a new interface group.
IP Type This field displays IPv4 for the type of the DHCP IP address. At the time of writing, it is not
allowed to select other type.
Select Device Info Select a device or computer from the drop-down list or select Manual Input to manually enter
a device’s MAC address and IP address in the following fields.
MAC Address If you select Manual Input, enter the MAC address of a computer on your LAN.
IP Address If you select Manual Input, enter the IP address that you want to assign to the computer on
your LAN with the MAC address that you will also specify.
OK Click OK to save your changes.
Cancel Click Cancel to exit this screen without saving.
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Use the following screen to configure the UPnP settings on your VMG. Click Network Setting > Home
Networking > UPnP to display the screen shown next.
Figure 56 Network Setting > Home Networking > UPnP
The following table describes the labels in this screen.
8.4.1 Turning On UPnP in Windows 7 Example
This section shows you how to use the UPnP feature in Windows 7. UPnP server is installed in Windows 7.
Activate UPnP on the VMG.
Make sure the computer is connected to a LAN port of the VMG. Turn on your computer and the VMG.
1Click the start icon, Control Panel and then the Network and Sharing Center.
Table 33 Network Setting > Home Networking > UPnP
LABEL DESCRIPTION
UPnP Select Enable to activate UPnP. Be aware that anyone could use a UPnP application to open
the web configurator's login screen without entering the VMG's IP address (although you must
still enter the password to access the web configurator).
UPnP NAT-T Select Enable to allow UPnP-enabled applications to automatically configure the VMG so that
they can communicate through the VMG by using NAT traversal. UPnP applications
automatically reserve a NAT forwarding port in order to communicate with another UPnP
enabled device; this eliminates the need to manually configure port forwarding for the UPnP
enabled application.
The table below displays the NAT port forwarding rules added automatically by UPnP NAT-T.
# This is the index number of the UPnP NAT-T connection.
Description This is the description of the UPnP NAT-T connection.
Destination IP
Address
This is the IP address of the other connected UPnP-enabled device.
External Port This is the external port number that identifies the service.
Internal Port This is the internal port number that identifies the service.
Protocol This is the transport layer protocol used for the service.
Apply Click Apply to save your changes.
Cancel Click Cancel to exit this screen without saving.
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2Click Change Advanced Sharing Settings.
3Select Turn on network discovery and click Save Changes. Network discovery allows your computer to
find other computers and devices on the network and other computers on the network to find your
computer. This makes it easier to share files and printers.
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8.5 The Additional Subnet Screen
Use the Additional Subnet screen to configure IP alias and public static IP.
IP alias allows you to partition a physical network into different logical networks over the same Ethernet
interface. The VMG supports multiple logical LAN interfaces via its physical Ethernet interface with the
VMG itself as the gateway for the LAN network. When you use IP alias, you can also configure firewall
rules to control access to the LAN's logical network (subnet).
If your ISP provides the Public LAN service, the VMG may use an LAN IP address that can be accessed
from the WAN.
Click Network Setting > Home Networking > Additional Subnet to display the screen shown next.
Figure 57 Network Setting > Home Networking > Additional Subnet
The following table describes the labels in this screen.
Table 34 Network Setting > Home Networking > Additional Subnet
LABEL DESCRIPTION
IP Alias Setup
Group Name Select the interface group name for which you want to configure the IP alias settings. See
Chapter 13 on page 183 for how to create a new interface group.
Active Select Enable to configure a LAN network for the VMG.
IPv4 Address Enter the IP address of your VMG in dotted decimal notation.
Subnet Mask Enter the subnet mask of your network in dotted decimal notation, for example 255.255.255.0
(factory default).
Public LAN
Active Select Enable to turn on the Public LAN feature. Your ISP must support Public LAN and Static IP.
IPv4 Address Enter the public IP address provided by your ISP.
Subnet Mask Enter the public IP subnet mask provided by your ISP.
Offer Public IP
by DHCP
Select Enable to allow the VMG to provide public IP addresses by DHCP server.
Enable ARP
Proxy
Select Enable to activate the ARP (Address Resolution Protocol) proxy.
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8.6 The STB Vendor ID Screen
Set Top Box (STB) devices with dynamic IP addresses sometimes don’t renew their IP addresses before
the lease time expires. This could lead to IP address conflicts if the STB continues to use an IP address that
gets assigned to another device. Use this screen to configure the Vendor IDs of connected STBs, which
have the VMG automatically created static DHCP entries for them when they request IP addresses.
Click Network Setting > Home Networking > STB Vendor ID to open this screen.
Figure 58 Network Setting > Home Networking > STB Vendor ID
The following table describes the labels in this screen.
8.7 The Wake on LAN Screen
Use this screen to turn on a device on the LAN network. To use this feature, the remote device must also
support Wake On LAN.
You need to know the MAC address of the LAN device. It may be on a label on the device or in its
documentation.
Click Network Setting > Home Networking > Wake on LAN to open this screen.
Figure 59 Network Setting > Home Networking > Wake on LAN
Apply Click Apply to save your changes.
Cancel Click Cancel to exit this screen without saving.
Table 34 Network Setting > Home Networking > Additional Subnet (continued)
LABEL DESCRIPTION
Table 35 Network Setting > Home Networking > STB Vendor ID
LABEL DESCRIPTION
Vendor ID 1~5 These are STB’s Vendor Class Identifiers (DHCP option 60). A Vendor Class Identifier is usually
used to inform the DHCP server a DHCP client’s vendor and functionality.
Apply Click Apply to save your changes.
Cancel Click Cancel to exit this screen without saving.
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The following table describes the labels in this screen.
8.8 The TFTP Server Name Screen
Use the TFTP Server Name screen to set the TFTP server address which is passed to the clients using DHCP
option 66. The DHCP clients in the VMG local network, such as STB devices, can then use the TFTP server
address or domain name for configuration file download. RFC 2132 defines the option 66 open
standard. DHCP option 66 carries the IP address or the domain name of a single TFTP server.
Click Network Setting > Home Networking > TFTP Server Name to open this screen.
Figure 60 Network Setting > Home Networking > TFTP Server Name
The following table describes the labels in this screen.
8.9 Technical Reference
This section provides some technical background information about the topics covered in this chapter.
8.9.1 LANs, WANs and the VMG
The actual physical connection determines whether the VMG ports are LAN or WAN ports. There are two
separate IP networks, one inside the LAN network and the other outside the WAN network as shown
next.
Table 36 Network Setting > Home Networking > Wake on LAN
LABEL DESCRIPTION
Wake by
Address
Select Manual and enter the IP address or MAC address of the device to turn it on remotely. The
drop-down list also lists the IP addresses that can be found in the VMG’s ARP table. Select an IP
address and it will then automatically update the IP address and MAC address in the following
fields.
IP Address Enter the IPv4 IP address of the device to turn it on.
MAC Address Enter the MAC address of the device to turn it on. A MAC address consists of six hexadecimal
character pairs.
Wake up Click this to send a wake up packet to wake up the specified device.
Table 37 Network Setting > Home Networking > TFTP Server Name
LABEL DESCRIPTION
TFTP Server
Name
Enter the IP address or the domain name of a single TFTP server.
Apply Click Apply to save your changes.
Cancel Click Cancel to exit this screen without saving.
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Figure 61 LAN and WAN IP Addresses
8.9.2 DHCP Setup
DHCP (Dynamic Host Configuration Protocol, RFC 2131 and RFC 2132) allows individual clients to obtain
TCP/IP configuration at start-up from a server. You can configure the VMG as a DHCP server or disable it.
When configured as a server, the VMG provides the TCP/IP configuration for the clients. If you turn DHCP
service off, you must have another DHCP server on your LAN, or else the computer must be manually
configured.
IP Pool Setup
The VMG is pre-configured with a pool of IP addresses for the DHCP clients (DHCP Pool). See the product
specifications in the appendices. Do not assign static IP addresses from the DHCP pool to your LAN
computers.
8.9.3 DNS Server Addresses
DNS (Domain Name System) maps a domain name to its corresponding IP address and vice versa. The
DNS server is extremely important because without it, you must know the IP address of a computer
before you can access it. The DNS server addresses you enter when you set up DHCP are passed to the
client machines along with the assigned IP address and subnet mask.
There are two ways that an ISP disseminates the DNS server addresses.
• The ISP tells you the DNS server addresses, usually in the form of an information sheet, when you sign
up. If your ISP gives you DNS server addresses, enter them in the DNS Server fields in the DHCP Setup
screen.
• Some ISPs choose to disseminate the DNS server addresses using the DNS server extensions of IPCP (IP
Control Protocol) after the connection is up. If your ISP did not give you explicit DNS servers, chances
are the DNS servers are conveyed through IPCP negotiation. The VMG supports the IPCP DNS server
extensions through the DNS proxy feature.
Please note that DNS proxy works only when the ISP uses the IPCP DNS server extensions. It does not
mean you can leave the DNS servers out of the DHCP setup under all circumstances. If your ISP gives
you explicit DNS servers, make sure that you enter their IP addresses in the DHCP Setup screen.
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8.9.4 LAN TCP/IP
The VMG has built-in DHCP server capability that assigns IP addresses and DNS servers to systems that
support DHCP client capability.
IP Address and Subnet Mask
Similar to the way houses on a street share a common street name, so too do computers on a LAN share
one common network number.
Where you obtain your network number depends on your particular situation. If the ISP or your network
administrator assigns you a block of registered IP addresses, follow their instructions in selecting the IP
addresses and the subnet mask.
If the ISP did not explicitly give you an IP network number, then most likely you have a single user
account and the ISP will assign you a dynamic IP address when the connection is established. If this is
the case, it is recommended that you select a network number from 192.168.0.0 to 192.168.255.0 and
you must enable the Network Address Translation (NAT) feature of the VMG. The Internet Assigned
Number Authority (IANA) reserved this block of addresses specifically for private use; please do not use
any other number unless you are told otherwise. Let's say you select 192.168.1.0 as the network number;
which covers 254 individual addresses, from 192.168.1.1 to 192.168.1.254 (zero and 255 are reserved). In
other words, the first three numbers specify the network number while the last number identifies an
individual computer on that network.
Once you have decided on the network number, pick an IP address that is easy to remember, for
instance, 192.168.1.1, for your VMG, but make sure that no other device on your network is using that IP
address.
The subnet mask specifies the network number portion of an IP address. Your VMG will compute the
subnet mask automatically based on the IP address that you entered. You don't need to change the
subnet mask computed by the VMG unless you are instructed to do otherwise.
Private IP Addresses
Every machine on the Internet must have a unique address. If your networks are isolated from the
Internet, for example, only between your two branch offices, you can assign any IP addresses to the
hosts without problems. However, the Internet Assigned Numbers Authority (IANA) has reserved the
following three blocks of IP addresses specifically for private networks:
• 10.0.0.0 — 10.255.255.255
• 172.16.0.0 — 172.31.255.255
• 192.168.0.0 — 192.168.255.255
You can obtain your IP address from the IANA, from an ISP or it can be assigned from a private network.
If you belong to a small organization and your Internet access is through an ISP, the ISP can provide you
with the Internet addresses for your local networks. On the other hand, if you are part of a much larger
organization, you should consult your network administrator for the appropriate IP addresses.
Note: Regardless of your particular situation, do not create an arbitrary IP address; always
follow the guidelines above. For more information on address assignment, please refer
to RFC 1597, “Address Allocation for Private Internets” and RFC 1466, “Guidelines for
Management of IP Address Space”.
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CHAPTER 9
Routing
9.1 Overview
The VMG usually uses the default gateway to route outbound traffic from computers on the LAN to the
Internet. To have the VMG send data to devices not reachable through the default gateway, use static
routes.
For example, the next figure shows a computer (A) connected to the VMG’s LAN interface. The VMG
routes most traffic from A to the Internet through the VMG’s default gateway (R1). You create one static
route to connect to services offered by your ISP behind router R2. You create another static route to
communicate with a separate network behind a router R3 connected to the LAN.
Figure 62 Example of Routing Topology
9.2 The Routing Screen
Use this screen to view and configure the static route rules on the VMG. Click Network Setting > Routing
> Static Route to open the following screen.
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Figure 63 Network Setting > Routing > Static Route
The following table describes the labels in this screen.
9.2.1 Add/Edit Static Route
Use this screen to add or edit a static route. Click Add new static route in the Routing screen or the Edit
icon next to the static route you want to edit. The screen shown next appears.
Figure 64 Routing: Add/Edit
Table 38 Network Setting > Routing > Static Route
LABEL DESCRIPTION
Add new static
route
Click this to configure a new static route.
#This is the index number of the entry.
Status This field displays whether the static route is active or not. A yellow bulb signifies that this route is
active. A gray bulb signifies that this route is not active.
Name This is the name that describes or identifies this route.
Destination IP This parameter specifies the IP network address of the final destination. Routing is always based
on network number.
Subnet Mask/
Prefix Length
This parameter specifies the IP network subnet mask of the final destination.
Gateway This is the IP address of the gateway. The gateway is a router or switch on the same network
segment as the device's LAN or WAN port. The gateway helps forward packets to their
destinations.
Interface This is the WAN interface used for this static route.
Modify Click the Edit icon to edit the static route on the VMG.
Click the Delete icon to remove a static route from the VMG. A window displays asking you to
confirm that you want to delete the route.
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The following table describes the labels in this screen.
9.3 The DNS Route Screen
Use this screen to view and configure DNS routes on the VMG. Click Network Setting > Routing > DNS
Route to open the following screen.
Figure 65 Network Setting > Routing > DNS Route
The following table describes the labels in this screen.
Table 39 Routing: Add/Edit
LABEL DESCRIPTION
Active This field allows you to activate/deactivate this static route.
Select Enable to activate the static route. Select Disable to deactivate this static route without
having to delete the entry.
Route Name Enter a descriptive name for the static route.
IP Type Select whether your IP type is IPv4 or IPv6.
Destination IP
Address
Enter the IPv4 or IPv6 network address of the final destination.
IP Subnet Mask If you are using IPv4 and need to specify a route to a single host, use a subnet mask of
255.255.255.255 in the subnet mask field to force the network number to be identical to the host
ID. Enter the IP subnet mask here.
Use Gateway IP
Address
The gateway is a router or switch on the same network segment as the device's LAN or WAN
port. The gateway helps forward packets to their destinations.
If you want to use the gateway IP address, select Enable.
Gateway IP
Address
Enter the IP address of the gateway.
Use Interface Select the WAN interface you want to use for this static route.
OK Click OK to save your changes.
Cancel Click Cancel to exit this screen without saving.
Table 40 Network Setting > Routing > DNS Route
LABEL DESCRIPTION
Add New DNS
Route
Click this to add a new DNS route.
#This is the index number of a DNS route.
Status This field displays whether the DNS route is active or not. A yellow bulb signifies that this DNS route
is active. A gray bulb signifies that this DNS route is not active.
Domain Name This is the host name or domain name of the DNS route entry.
WAN Interface This is the WAN connection through which the VMG forwards DNS requests for this domain name.
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9.3.1 The DNS Route Add Screen
You can manually add the VMG’s DNS route entry. Click Add New DNS Route in the Network Setting >
Routing > DNS Route screen. The screen shown next appears.
Figure 66 DNS Route Add
The following table describes the labels in this screen.
9.4 The Policy Route Screen
Traditionally, routing is based on the destination address only and the VMG takes the shortest path to
forward a packet. Policy route allows the VMG to override the default routing behavior and alter the
packet forwarding based on the policy defined by the network administrator. Policy-based routing is
applied to outgoing packets, prior to the normal routing.
You can use source-based policy forwarding to direct traffic from different users through different
connections or distribute traffic among multiple paths for load sharing.
Subnet Mask This is the subnet mask of the DNS route entry.
Modify Click the Edit icon to modify the DNS route.
Click the Delete icon to delete the DNS route.
Table 40 Network Setting > Routing > DNS Route (continued)
LABEL DESCRIPTION
Table 41 DNS Route Add
LABEL DESCRIPTION
Active Select Enable or Disable to activate or deactivate the DNS route.
Domain Name Enter the domain name of the DNS route entry.
Subnet Mask Enter the subnet mask of the DNS route entry.
WAN Interface Select the WAN connection through which the VMG forwards DNS requests for this domain
name. WWAN means the wireless cellular interface.
OK Click this to save your changes.
Cancel Click this to exit this screen without saving any changes.
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The Policy Route screen let you view and configure routing policies on the VMG. Click N etwork Setting >
Routing > Policy Route to open the following screen.
Figure 67 Network Setting > Routing > Policy Route
The following table describes the labels in this screen.
Table 42 Network Setting > Routing >Policy Route
LABEL DESCRIPTION
Add New Policy
Route
Click this to create a new policy forwarding rule.
#This is the index number of the entry.
Status This field displays whether the DNS route is active or not. A yellow bulb signifies that this DNS route
is active. A gray bulb signifies that this DNS route is not active.
Name This is the name of the rule.
Source IP This is the source IP address.
Source Subnet
Mask
This is the source subnet mask address.
Protocol This is the transport layer protocol.
Source Port This is the source port number.
Source MAC This is the source MAC address.
Source
Interface
This is the interface from which the matched traffic is sent.
WAN Interface This is the WAN interface through which the traffic is routed.
Modify Click the Edit icon to edit this policy.
Click the Delete icon to remove a policy from the VMG. A window displays asking you to confirm
that you want to delete the policy.
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9.4.1 Add/Edit Policy Route
Click Add New Policy Route in the Policy Route screen or click the Edit icon next to a policy. Use this
screen to configure the required information for a policy route.
Figure 68 Policy Route: Add/Edit
The following table describes the labels in this screen.
9.5 RIP
Routing Information Protocol (RIP, RFC 1058 and RFC 1389) allows a device to exchange routing
information with other routers.
Table 43 Policy Route: Add/Edit
LABEL DESCRIPTION
Active Select Enable or Disable to activate or deactivate the policy route.
Route Name Enter a descriptive name of up to 8 printable English keyboard characters, not including spaces.
Source IP
Address
Enter the source IP address.
Source Subnet
Mask
Enter the source subnet mask address.
Protocol Select the transport layer protocol (TCP or UDP).
Source Port Enter the source port number.
Source MAC Enter the source MAC address.
Source Interface
(ex: br0 or
LAN1~LAN4)
Type the name of the interface from which the matched traffic is sent.
WAN Interface Select a WAN interface through which the traffic is sent. You must have the WAN interface(s)
already configured in the Broadband screens. WWAN means the wireless cellular interface.
OK Click OK to save your changes.
Cancel Click Cancel to exit this screen without saving.
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9.5.1 The RIP Screen
Click Network Setting > Routing > RIP to open the RIP screen.
Figure 69 RIP
The following table describes the labels in this screen.
Table 44 RIP
LABEL DESCRIPTION
#This is the index of the interface in which the RIP setting is used.
Interface This is the name of the interface in which the RIP setting is used.
Version The RIP version controls the format and the broadcasting method of the RIP packets that the
VMG sends (it recognizes both formats when receiving). RIP version 1 is universally supported but
RIP version 2 carries more information. RIP version 1 is probably adequate for most networks,
unless you have an unusual network topology.
Operation Select Passive to have the VMG update the routing table based on the RIP packets received
from neighbors but not advertise its route information to other routers in this interface.
Select Active to have the VMG advertise its route information and also listen for routing updates
from neighboring routers.
Enable Select the check box to activate the settings.
Disable Default
Gateway
Select the check box to set the VMG to not send the route information to the default gateway.
Apply Click Apply to save your changes back to the VMG.
Cancel Click Cancel to restore your previously saved settings.
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CHAPTER 10
Quality of Service (QoS)
10.1 Overview
Quality of Service (QoS) refers to both a network’s ability to deliver data with minimum delay, and the
networking methods used to control the use of bandwidth. Without QoS, all traffic data is equally likely
to be dropped when the network is congested. This can cause a reduction in network performance and
make the network inadequate for time-critical application such as video-on-demand.
Configure QoS on the VMG to group and prioritize application traffic and fine-tune network
performance. Setting up QoS involves these steps:
1Configure classifiers to sort traffic into different flows.
2Assign priority and define actions to be performed for a classified traffic flow.
The VMG assigns each packet a priority and then queues the packet accordingly. Packets assigned a
high priority are processed more quickly than those with low priority if there is congestion, allowing time-
sensitive applications to flow more smoothly. Time-sensitive applications include both those that require
a low level of latency (delay) and a low level of jitter (variations in delay) such as Voice over IP (VoIP) or
Internet gaming, and those for which jitter alone is a problem such as Internet radio or streaming video.
This chapter contains information about configuring QoS and editing classifiers.
10.1.1 What You Can Do in this Chapter
• Use the General screen to enable or disable QoS and set the upstream bandwidth (Section 10.3 on
page 147).
• Use the Queue Setup screen to configure QoS queue assignment (Section 10.4 on page 148).
• Use the Classification Setup screen to add, edit or delete QoS classifiers (Section 10.5 on page 151).
• Use the Shaper Setup screen to limit outgoing traffic transmission rate on the selected interface
(Section 10.6 on page 155).
• Use the Policer Setup screen to control incoming traffic transmission rate and bursts ( Section 10.6 on
page 155).
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10.2 What You Need to Know
The following terms and concepts may help as you read through this chapter.
QoS versus Cos
QoS is used to prioritize source-to-destination traffic flows. All packets in the same flow are given the
same priority. CoS (class of service) is a way of managing traffic in a network by grouping similar types of
traffic together and treating each type as a class. You can use CoS to give different priorities to different
packet types.
CoS technologies include IEEE 802.1p layer 2 tagging and DiffServ (Differentiated Services or DS). IEEE
802.1p tagging makes use of three bits in the packet header, while DiffServ is a new protocol and
defines a new DS field, which replaces the eight-bit ToS (Type of Service) field in the IP header.
Tagging and Marking
In a QoS class, you can configure whether to add or change the DSCP (DiffServ Code Point) value, IEEE
802.1p priority level and VLAN ID number in a matched packet. When the packet passes through a
compatible network, the networking device, such as a backbone switch, can provide specific
treatment or service based on the tag or marker.
Traffic Shaping
Bursty traffic may cause network congestion. Traffic shaping regulates packets to be transmitted with a
pre-configured data transmission rate using buffers (or queues). Your VMG uses the Token Bucket
algorithm to allow a certain amount of large bursts while keeping a limit at the average rate.
Traffic
Time
Traffic Rate
Traffic
Time
Traffic Rate
(Before Traffic Shaping) (After Traffic Shaping)
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Traffic Policing
Traffic policing is the limiting of the input or output transmission rate of a class of traffic on the basis of
user-defined criteria. Traffic policing methods measure traffic flows against user-defined criteria and
identify it as either conforming, exceeding or violating the criteria.
The VMG supports three incoming traffic metering algorithms: Token Bucket Filter (TBF), Single Rate Two
Color Maker (srTCM), and Two Rate Two Color Marker (trTCM). You can specify actions which are
performed on the colored packets. See Section 10.8 on page 158 for more information on each
metering algorithm.
10.3 The Quality of Service General Screen
Click Network Setting > QoS > General to open the screen as shown next.
Use this screen to enable or disable QoS and set the upstream bandwidth. See Section 10.1 on page 145
for more information.
Figure 70 Network Settings > QoS > General
Traffic
Time
Traffic Rate
Traffic
Time
Traffic Rate
(Before Traffic Policing) (After Traffic Policing)
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The following table describes the labels in this screen.
10.4 The Queue Setup Screen
Click Network Setting > QoS > Queue Setup to open the screen as shown next.
Use this screen to configure QoS queue assignment.
Table 45 Network Setting > QoS > General
LABEL DESCRIPTION
QoS Select the Enable check box to turn on QoS to improve your network performance.
WAN Managed
Upstream
Bandwidth
Enter the amount of upstream bandwidth for the WAN interfaces that you want to allocate using
QoS.
The recommendation is to set this speed to match the interfaces’ actual transmission speed. For
example, set the WAN interfaces’ speed to 100000 kbps if your Internet connection has an
upstream transmission speed of 100 Mbps.
You can set this number higher than the interfaces’ actual transmission speed. The VMG uses up
to 95% of the DSL port’s actual upstream transmission speed even if you set this number higher
than the DSL port’s actual transmission speed.
You can also set this number lower than the interfaces’ actual transmission speed. This will cause
the VMG to not use some of the interfaces’ available bandwidth.
If you leave this field blank, the VMG automatically sets this number to be 95% of the WAN
interfaces’ actual upstream transmission speed.
LAN Managed
Downstream
Bandwidth
Enter the amount of downstream bandwidth for the LAN interfaces (including WLAN) that you
want to allocate using QoS.
The recommendation is to set this speed to match the WAN interfaces’ actual transmission
speed. For example, set the LAN managed downstream bandwidth to 100000 kbps if you use a
100 Mbps wired Ethernet WAN connection.
You can also set this number lower than the WAN interfaces’ actual transmission speed. This will
cause the VMG to not use some of the interfaces’ available bandwidth.
If you leave this field blank, the VMG automatically sets this to the LAN interfaces’ maximum
supported connection speed.
Upstream Traffic
Priority Assigned
by
Select how the VMG assigns priorities to various upstream traffic flows.
•None: Disables auto priority mapping and has the VMG put packets into the queues
according to your classification rules. Traffic which does not match any of the classification
rules is mapped into the default queue with the lowest priority.
•Ethernet Priority: Automatically assign priority based on the IEEE 802.1p priority level.
•IP Prece dence: Automatically assign priority based on the first three bits of the TOS field in the
IP header.
•Packet Length: Automatically assign priority based on the packet size. Smaller packets get
higher priority since control, signaling, VoIP, internet gaming, or other real-time packets are
usually small while larger packets are usually best effort data packets like file transfers.
Apply Click Apply to save your changes.
Cancel Click Cancel to restore your previously saved settings.
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Figure 71 Network Setting > QoS > Queue Setup
The following table describes the labels in this screen.
Table 46 Network Setting > QoS > Queue Setup
LABEL DESCRIPTION
Add New
Queue
Click this button to create a new queue entry.
#This is the index number of the entry.
Status This field displays whether the queue is active or not. A yellow bulb signifies that this queue is
active. A gray bulb signifies that this queue is not active.
Name This shows the descriptive name of this queue.
Interface This shows the name of the VMG’s interface through which traffic in this queue passes.
Discipline This shows the queuing method of this queue.
Priority This shows the priority of this queue.
Weight This shows the weight of this queue.
Buffer
Management
This shows the queue management algorithm used for this queue.
Queue management algorithms determine how the VMG should handle packets when it
receives too many (network congestion).
Rate Limit This shows the maximum transmission rate allowed for traffic on this queue.
Modify Click the Edit icon to edit the queue.
Click the Delete icon to delete an existing queue. Note that subsequent rules move up by one
when you take this action.
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10.4.1 Editing a QoS Queue
Click the edit icon in the Queue Setup screen to configure a queue.
Figure 72 Queue Setup: Edit
The following table describes the labels in this screen.
Table 47 Queue Setup: Add
LABEL DESCRIPTION
Name Enter the descriptive name of this queue.
Interface Select the interface to which this queue is applied.
This field is read-only if you are editing the queue.
Discipline Select SPQ (Strict Priority Queuing) or WRR (Weighted Round Robin).
Strict Priority Queuing (SP) services queues based on priority only. When the highest priority
queue empties, traffic on the next highest-priority queue begins. Q1 has the highest priority and
Q4 the lowest.
Weighted Round Robin Scheduling (WRR) services queues on a rotating basis based on their
queue weight (the number you configure in the queue Weight field).Queues with larger weights
get more service than queues with smaller weights
Priority Select the priority level (from 1 to 7) of this queue.
The smaller the number, the higher the priority level. Traffic assigned to higher priority queues
gets through faster while traffic in lower priority queues is dropped if the network is congested.
Weight Select the weight (from 1 to 8) of this queue.
If two queues have the same priority level, the VMG divides the bandwidth across the queues
according to their weights. Queues with larger weights get more bandwidth than queues with
smaller weights.
Buffer
Management
This field displays Drop Tail (DT). Drop Tail (DT) is a simple queue management algorithm that
allows the VMG buffer to accept as many packets as it can until it is full. Once the buffer is full,
new packets that arrive are dropped until there is space in the buffer again (packets are
transmitted out of it).
Rate Limit Specify the maximum transmission rate (in Kbps) allowed for traffic on this queue.
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10.5 The Classification Setup Screen
Use this screen to add, edit or delete QoS classifiers. A classifier groups traffic into data flows according
to specific criteria such as the source address, destination address, source port number, destination port
number or incoming interface. For example, you can configure a classifier to select traffic from the
same protocol port (such as Telnet) to form a flow.
You can give different priorities to traffic that the VMG forwards out through the WAN interface. Give
high priority to voice and video to make them run more smoothly. Similarly, give low priority to many
large file downloads so that they do not reduce the quality of other applications.
Click Network Setting > QoS > Classification Setup to open the following screen.
Figure 73 Network Setting > QoS > Classification Setup
The following table describes the labels in this screen.
OK Click OK to save your changes.
Cancel Click Cancel to exit this screen without saving.
Table 47 Queue Setup: Add (continued)
LABEL DESCRIPTION
Table 48 Network Setting > QoS > Classification Setup
LABEL DESCRIPTION
Add New
Classification
Click this to create a new classifier.
Order This is the index number of the entry. The classifiers are applied in order of their numbering.
Status This field displays whether the classifier is active or not. A yellow bulb signifies that this classifier
is active. A gray bulb signifies that this classifier is not active.
Class Name This is the name of the classifier.
Classification
Criteria
This shows criteria specified in this classifier, for example the interface from which traffic of this
class should come and the source MAC address of traffic that matches this classifier.
DSCP Mark This is the DSCP number added to traffic of this classifier.
802.1P Mark This is the IEEE 802.1p priority level assigned to traffic of this classifier.
VLAN ID Tag This is the VLAN ID number assigned to traffic of this classifier.
To Queue This is the name of the queue in which traffic of this classifier is put.
Modify Click the Edit icon to edit the classifier.
Click the Delete icon to delete an existing classifier. Note that subsequent rules move up by
one when you take this action.
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10.5.1 Add/Edit QoS Class
Click Add New Clas sification in the Classification Setup screen or the Edit icon next to a classifier to open
the following screen.
Figure 74 Classification Setup: Add/Edit
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The following table describes the labels in this screen.
Table 49 Classification Setup: Add/Edit
LABEL DESCRIPTION
Step1: Class Configuration
Active Select Enable or Disable to activate or deactivate the classifier.
Class Name Enter a descriptive name of up to 15 printable English keyboard characters, not including
spaces.
Classification
Order
Select an existing number for where you want to put this classifier to move the classifier to the
number you selected after clicking Apply.
Select Last to put this rule in the back of the classifier list.
Step2: Criteria Configuration
Basic
From
Interface If you want to classify the traffic by an ingress interface, select an interface from the From
Interface drop-down list box.
Ether Type Select a predefined application to configure a class for the matched traffic.
If you select IP, you also need to configure source or destination MAC address, IP address, DHCP
options, DSCP value or the protocol type.
If you select 802.1Q, you can configure an 802.1p priority level.
Source
Address Select the check box and enter the source IP address in dotted decimal notation. A blank
source IP address means any source IP address.
Subnet Mask Enter the source subnet mask.
Port Range If you select TCP or UDP in the IP Protocol field, select the check box and enter the port
number(s) of the source.
MAC Select the check box and enter the source MAC address of the packet.
MAC Mask Type the mask for the specified MAC address to determine which bits a packet’s MAC address
should match.
Enter “f” for each bit of the specified source MAC address that the traffic’s MAC address should
match. Enter “0” for the bit(s) of the matched traffic’s MAC address, which can be of any
hexadecimal character(s). For example, if you set the MAC address to 00:13:49:00:00:00 and the
mask to ff:ff:ff:00:00:00, a packet with a MAC address of 00:13:49:12:34:56 matches this criteria.
Exclude Select this option to exclude the packets that match the specified criteria from this classifier.
Destination
Address Select the check box and enter the destination IP address in dotted decimal notation. A blank
source IP address means any source IP address.
Subnet Mask Enter the destination subnet mask.
Port Range If you select TCP or UDP in the IP Protocol field, select the check box and enter the port
number(s) of the destination.
MAC Select the check box and enter the destination MAC address of the packet.
MAC Mask Type the mask for the specified MAC address to determine which bits a packet’s MAC address
should match.
Enter “f” for each bit of the specified destination MAC address that the traffic’s MAC address
should match. Enter “0” for the bit(s) of the matched traffic’s MAC address, which can be of any
hexadecimal character(s). For example, if you set the MAC address to 00:13:49:00:00:00 and the
mask to ff:ff:ff:00:00:00, a packet with a MAC address of 00:13:49:12:34:56 matches this criteria.
Exclude Select this option to exclude the packets that match the specified criteria from this classifier.
Others
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Service This field is available only when you select IP in the Ether Type field.
This field simplifies classifier configuration by allowing you to select a predefined application.
When you select a predefined application, you do not configure the rest of the filter fields.
IP Protocol This field is available only when you select IP in the Ether Type field.
Select this option and select the protocol (service type) from TCP, UDP, ICMP or IGMP. If you
select User defined, enter the protocol (service type) number.
DHCP This field is available only when you select IP in the Ether Type field.
Select this option and select a DHCP option.
If you select Vendor Class ID (DHCP Option 60), enter the Vendor Class Identifier (Option 60) of
the matched traffic, such as the type of the hardware or firmware.
If you select Client ID (DHCP Option 61), enter the Identity Association IDentifier (IAD Option 61)
of the matched traffic, such as the MAC address of the device.
If you select User Class ID (DHCP Option 77), enter a string that identifies the user’s category or
application type in the matched DHCP packets.
If you select Vendor Specific Info (DHCP Option 125), enter the vendor specific information of
the matched traffic, such as the product class, model name, and serial number of the device.
IP Packet
Length This field is available only when you select IP in the Ether Type field.
Select this option and enter the minimum and maximum packet length (from 46 to 1500) in the
fields provided.
DSCP This field is available only when you select IP in the Ether Type field.
Select this option and specify a DSCP (DiffServ Code Point) number between 0 and 63 in the
field provided.
802.1P This field is available only when you select 802.1Q in the Ether Type field.
Select this option and select a priority level (between 0 and 7) from the drop-down list box.
"0" is the lowest priority level and "7" is the highest.
VLAN ID This field is available only when you select 802.1Q in the Ether Type field.
Select this option and specify a VLAN ID number.
TCP ACK This field is available only when you select IP in the Ether Type field.
If you select this option, the matched TCP packets must contain the ACK (Acknowledge) flag.
Exclude Select this option to exclude the packets that match the specified criteria from this classifier.
Step3: Packet Modification
DSCP Mark This field is available only when you select IP in the Ether Type field.
If you select Remark, enter a DSCP value with which the VMG replaces the DSCP field in the
packets.
If you select Unchange, the VMG keep the DSCP field in the packets.
802.1P Mark Select a priority level with which the VMG replaces the IEEE 802.1p priority field in the packets.
If you select Unchange, the VMG keep the 802.1p priority field in the packets.
VLAN ID Tag If you select Remark, enter a VLAN ID number with which the VMG replaces the VLAN ID of the
frames.
If you select Remove, the VMG deletes the VLAN ID of the frames before forwarding them out.
If you select Add, the VMG treat all matched traffic untagged and add a second VLAN ID.
If you select Unchange, the VMG keep the VLAN ID in the packets.
Table 49 Classification Setup: Add/Edit (continued)
LABEL DESCRIPTION
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10.6 The QoS Shaper Setup Screen
This screen shows that you can use the token bucket algorithm to allow a certain amount of large bursts
while keeping a limit for processing outgoing traffic at the average rate. Click Network Setting > QoS >
Shaper Setup. The screen appears as shown.
Figure 75 Network Setting > QoS > Shaper Setup
The following table describes the labels in this screen.
Step4: Class Routing
Forward to
Interface
Select a WAN interface through which traffic of this class will be forwarded out. If you select
Unchange, the VMG forward traffic of this class according to the default routing table.
Step5: Outgoing Queue Selection
To Queue Index Select a queue that applies to this class.
You should have configured a queue in the Queue Setup screen already.
OK Click OK to save your changes.
Cancel Click Cancel to exit this screen without saving.
Table 49 Classification Setup: Add/Edit (continued)
LABEL DESCRIPTION
Table 50 Network Setting > QoS > Shaper Setup
LABEL DESCRIPTION
Add New
Shaper
Click this to create a new entry.
#This is the index number of the entry.
Status This field displays whether the shaper is active or not. A yellow bulb signifies that this policer is
active. A gray bulb signifies that this shaper is not active.
Outgoing
Interface
This shows the name of the VMG's interface through which traffic in this shaper applies.
Rate Limit (kbps) This shows the average rate limit of traffic bursts for this shaper.
Modify Click the Edit icon to edit the shaper.
Click the Delete icon to delete an existing shaper. Note that subsequent rules move up by one
when you take this action.
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10.6.1 Add/Edit a QoS Shaper
Click Add New Shaper in the Shaper Setup screen or the Edit icon next to a shaper to show the following
screen.
Figure 76 Shaper Setup: Add/Edit
The following table describes the labels in this screen.
10.7 The QoS Policer Setup Screen
Use this screen to view QoS policers that allow you to limit the transmission rate of incoming traffic and
apply actions, such as drop, pass, or modify the DSCP value for matched traffic. Click Network Setting >
QoS > Policer Setup. The screen appears as shown.
Figure 77 Network Setting > QoS > Policer Setup
The following table describes the labels in this screen.
Table 51 Shaper Setup: Add/Edit
LABEL DESCRIPTION
Active Select Enable or Disable to activate or deactivate the shaper.
Interface Select the VMG's interface through which traffic in this shaper applies.
Rate Limit Enter the average rate limit of traffic bursts for this shaper.
OK Click OK to save your changes.
Cancel Click Cancel to exit this screen without saving.
Table 52 Network Setting > QoS > Policer Setup
LABEL DESCRIPTION
Add New
Policer
Click this to create a new entry.
#This is the index number of the entry.
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10.7.1 Add/Edit a QoS Policer
Click Add New Policer in the Policer Setup screen or the Edit icon next to a policer to show the following
screen.
Figure 78 Policer Setup: Add/Edit
Status This field displays whether the policer is active or not. A yellow bulb signifies that this policer is
active. A gray bulb signifies that this policer is not active.
Name This field displays the descriptive name of this policer.
Regulated
Classes
This field displays the name of a QoS classifier
Meter Type This field displays the type of QoS metering algorithm used in this policer.
Rule These are the rates and burst sizes against which the policer checks the traffic of the member
QoS classes.
Action This shows the how the policer has the VMG treat different types of traffic belonging to the
policer’s member QoS classes.
Modify Click the Edit icon to edit the policer.
Click the Delete icon to delete an existing policer. Note that subsequent rules move up by one
when you take this action.
Table 52 Network Setting > QoS > Policer Setup (continued)
LABEL DESCRIPTION
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The following table describes the labels in this screen.
10.8 Technical Reference
The following section contains additional technical information about the VMG features described in
this chapter.
IEEE 802.1Q Tag
The IEEE 802.1Q standard defines an explicit VLAN tag in the MAC header to identify the VLAN
membership of a frame across bridges. A VLAN tag includes the 12-bit VLAN ID and 3-bit user priority.
Table 53 Policer Setup: Add/Edit
LABEL DESCRIPTION
Active Select Enable or Disable to activate or deactivate the policer.
Name Enter the descriptive name of this policer.
Meter Type This shows the traffic metering algorithm used in this policer.
The Simple Token Bucket algorithm uses tokens in a bucket to control when traffic can be
transmitted. Each token represents one byte. The algorithm allows bursts of up to b bytes which is
also the bucket size.
The Single Rate Three Color Marker (srTCM) is based on the token bucket filter and identifies
packets by comparing them to the Committed Information Rate (CIR), the Committed Burst Size
(CBS) and the Excess Burst Size (EBS).
The Two Rate Three Color Marker (trTCM) is based on the token bucket filter and identifies
packets by comparing them to the Committed Information Rate (CIR) and the Peak Information
Rate (PIR).
Committed
Rate
Specify the committed rate. When the incoming traffic rate of the member QoS classes is less
than the committed rate, the device applies the conforming action to the traffic.
Committed
Burst Size
Specify the committed burst size for packet bursts. This must be equal to or less than the peak
burst size (two rate three color) or excess burst size (single rate three color) if it is also configured.
This is the maximum size of the (first) token bucket in a traffic metering algorithm.
Conforming
Action
Specify what the VMG does for packets within the committed rate and burst size (green-marked
packets).
•Pass: Send the packets without modification.
•DSCP Mark: Change the DSCP mark value of the packets. Enter the DSCP mark value to use.
Non-
Conforming
Action
Specify what the VMG does for packets that exceed the excess burst size or peak rate and burst
size (red-marked packets).
•Drop: Discard the packets.
•DSCP Mark: Change the DSCP mark value of the packets. Enter the DSCP mark value to use.
The packets may be dropped if there is congestion on the network.
Available Class
Selected Class
Select a QoS classifier to apply this QoS policer to traffic that matches the QoS classifier.
Highlight a QoS classifier in the Available Class box and use the > button to move it to the
Selected Class box.
To remove a QoS classifier from the Selected Class box, select it and use the < button.
OK Click OK to save your changes.
Cancel Click Cancel to exit this screen without saving.
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The VLAN ID associates a frame with a specific VLAN and provides the information that devices need to
process the frame across the network.
IEEE 802.1p specifies the user priority field and defines up to eight separate traffic types. The following
table describes the traffic types defined in the IEEE 802.1d standard (which incorporates the 802.1p).
DiffServ
QoS is used to prioritize source-to-destination traffic flows. All packets in the flow are given the same
priority. You can use CoS (class of service) to give different priorities to different packet types.
DiffServ (Differentiated Services) is a class of service (CoS) model that marks packets so that they
receive specific per-hop treatment at DiffServ-compliant network devices along the route based on the
application types and traffic flow. Packets are marked with DiffServ Code Points (DSCPs) indicating the
level of service desired. This allows the intermediary DiffServ-compliant network devices to handle the
packets differently depending on the code points without the need to negotiate paths or remember
state information for every flow. In addition, applications do not have to request a particular service or
give advanced notice of where the traffic is going.
DSCP and Per-Hop Behavior
DiffServ defines a new Differentiated Services (DS) field to replace the Type of Service (TOS) field in the IP
header. The DS field contains a 2-bit unused field and a 6-bit DSCP field which can define up to 64
service levels. The following figure illustrates the DS field.
DSCP is backward compatible with the three precedence bits in the ToS octet so that non-DiffServ
compliant, ToS-enabled network device will not conflict with the DSCP mapping.
The DSCP value determines the forwarding behavior, the PHB (Per-Hop Behavior), that each packet
gets across the DiffServ network. Based on the marking rule, different kinds of traffic can be marked for
different kinds of forwarding. Resources can then be allocated according to the DSCP values and the
configured policies.
Table 54 IEEE 802.1p Priority Level and Traffic Type
PRIORITY
LEVEL TRAFFIC TYPE
Level 7 Typically used for network control traffic such as router configuration messages.
Level 6 Typically used for voice traffic that is especially sensitive to jitter (jitter is the variations in delay).
Level 5 Typically used for video that consumes high bandwidth and is sensitive to jitter.
Level 4 Typically used for controlled load, latency-sensitive traffic such as SNA (Systems Network
Architecture) transactions.
Level 3 Typically used for “excellent effort” or better than best effort and would include important business
traffic that can tolerate some delay.
Level 2 This is for “spare bandwidth”.
Level 1 This is typically used for non-critical “background” traffic such as bulk transfers that are allowed but
that should not affect other applications and users.
Level 0 Typically used for best-effort traffic.
DSCP (6 bits) Unused (2 bits)
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IP Precedence
Similar to IEEE 802.1p prioritization at layer-2, you can use IP precedence to prioritize packets in a layer-3
network. IP precedence uses three bits of the eight-bit ToS (Type of Service) field in the IP header. There
are eight classes of services (ranging from zero to seven) in IP precedence. Zero is the lowest priority
level and seven is the highest.
Automatic Priority Queue Assignment
If you enable QoS on the VMG, the VMG can automatically base on the IEEE 802.1p priority level, IP
precedence and/or packet length to assign priority to traffic which does not match a class.
The following table shows you the internal layer-2 and layer-3 QoS mapping on the VMG. On the VMG,
traffic assigned to higher priority queues gets through faster while traffic in lower index queues is
dropped if the network is congested
Token Bucket
The token bucket algorithm uses tokens in a bucket to control when traffic can be transmitted. The
bucket stores tokens, each of which represents one byte. The algorithm allows bursts of up to b bytes
which is also the bucket size, so the bucket can hold up to b tokens. Tokens are generated and added
into the bucket at a constant rate. The following shows how tokens work with packets:
• A packet can be transmitted if the number of tokens in the bucket is equal to or greater than the size
of the packet (in bytes).
• After a packet is transmitted, a number of tokens corresponding to the packet size is removed from
the bucket.
• If there are no tokens in the bucket, the VMG stops transmitting until enough tokens are generated.
• If not enough tokens are available, the VMG treats the packet in either one of the following ways:
In traffic shaping:
• Holds it in the queue until enough tokens are available in the bucket.
In traffic policing:
•Drops it.
• Transmits it but adds a DSCP mark. The VMG may drop these marked packets if the network is
overloaded.
Configure the bucket size to be equal to or less than the amount of the bandwidth that the interface
can support. It does not help if you set it to a bucket size over the interface’s capability. The smaller the
bucket size, the lower the data transmission rate and that may cause outgoing packets to be dropped.
A larger transmission rate requires a big bucket size. For example, use a bucket size of 10 kbytes to get
the transmission rate up to 10 Mbps.
Table 55 Internal Layer2 and Layer 3 QoS Mapping
PRIORITY ETHERNET PRIORITY
(802.1P) IP PRECEDENCE IP PACKET LENGTH
(BYTE)
4 001, 010 000XXX, 001XXX >1100
3 000, 011 010XXX, 011XXX 250-1100
2 100 100XXX
2 101 101XXX <250
1 (Highest) 110, 111 110XXX, 111XXX
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Single Rate Three Color Marker
The Single Rate Three Color Marker (srTCM, defined in RFC 2697) is a type of traffic policing that identifies
packets by comparing them to one user-defined rate, the Committed Information Rate (CIR), and two
burst sizes: the Committed Burst Size (CBS) and Excess Burst Size (EBS).
The srTCM evaluates incoming packets and marks them with one of three colors which refer to packet
loss priority levels. High packet loss priority level is referred to as red, medium is referred to as yellow and
low is referred to as green.
The srTCM is based on the token bucket filter and has two token buckets (CBS and EBS). Tokens are
generated and added into the bucket at a constant rate, called Committed Information Rate (CIR).
When the first bucket (CBS) is full, new tokens overflow into the second bucket (EBS).
All packets are evaluated against the CBS. If a packet does not exceed the CBS it is marked green.
Otherwise it is evaluated against the EBS. If it is below the EBS then it is marked yellow. If it exceeds the
EBS then it is marked red.
The following shows how tokens work with incoming packets in srTCM:
• A packet arrives. The packet is marked green and can be transmitted if the number of tokens in the
CBS bucket is equal to or greater than the size of the packet (in bytes).
• After a packet is transmitted, a number of tokens corresponding to the packet size is removed from
the CBS bucket.
• If there are not enough tokens in the CBS bucket, the VMG checks the EBS bucket. The packet is
marked yellow if there are sufficient tokens in the EBS bucket. Otherwise, the packet is marked red. No
tokens are removed if the packet is dropped.
Two Rate Three Color Marker
The Two Rate Three Color Marker (trTCM, defined in RFC 2698) is a type of traffic policing that identifies
packets by comparing them to two user-defined rates: the Committed Information Rate (CIR) and the
Peak Information Rate (PIR). The CIR specifies the average rate at which packets are admitted to the
network. The PIR is greater than or equal to the CIR. CIR and PIR values are based on the guaranteed
and maximum bandwidth respectively as negotiated between a service provider and client.
The trTCM evaluates incoming packets and marks them with one of three colors which refer to packet
loss priority levels. High packet loss priority level is referred to as red, medium is referred to as yellow and
low is referred to as green.
The trTCM is based on the token bucket filter and has two token buckets (Committed Burst Size (CBS)
and Peak Burst Size (PBS)). Tokens are generated and added into the two buckets at the CIR and PIR
respectively.
All packets are evaluated against the PIR. If a packet exceeds the PIR it is marked red. Otherwise it is
evaluated against the CIR. If it exceeds the CIR then it is marked yellow. Finally, if it is below the CIR then
it is marked green.
The following shows how tokens work with incoming packets in trTCM:
• A packet arrives. If the number of tokens in the PBS bucket is less than the size of the packet (in bytes),
the packet is marked red and may be dropped regardless of the CBS bucket. No tokens are removed
if the packet is dropped.
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• If the PBS bucket has enough tokens, the VMG checks the CBS bucket. The packet is marked green
and can be transmitted if the number of tokens in the CBS bucket is equal to or greater than the size
of the packet (in bytes). Otherwise, the packet is marked yellow.
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CHAPTER 11
Network Address Translation
(NAT)
11.1 Overview
This chapter discusses how to configure NAT on the VMG. NAT (Network Address Translation - NAT, RFC
1631) is the translation of the IP address of a host in a packet, for example, the source address of an
outgoing packet, used within one network to a different IP address known within another network.
11.1.1 What You Can Do in this Chapter
• Use the Port Forwarding screen to configure forward incoming service requests to the server(s) on your
local network (Section 11.2 on page 164).
• Use the Applications screen to forward incoming service requests to the server(s) on your local
network (Section 11.3 on page 167).
• Use the Port Triggering screen to add and configure the VMG’s trigger port settings (Section 11.4 on
page 168).
• Use the DMZ screen to configure a default server (Section 11.5 on page 171).
• Use the ALG screen to enable and disable the NAT and SIP (VoIP) ALG in the VMG (Section 11.6 on
page 172).
• Use the Address Mapping screen to configure the VMG's address mapping settings (Section 11.7 on
page 172).
• Use the Sessions screen to configure the VMG's maximum number of NAT sessions (Section 11.8 on
page 174).
11.1.2 What You Need To Know
Inside/Outside
Inside/outside denotes where a host is located relative to the VMG, for example, the computers of your
subscribers are the inside hosts, while the web servers on the Internet are the outside hosts.
Global/Local
Global/local denotes the IP address of a host in a packet as the packet traverses a router, for example,
the local address refers to the IP address of a host when the packet is in the local network, while the
global address refers to the IP address of the host when the same packet is traveling in the WAN side.
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NAT
In the simplest form, NAT changes the source IP address in a packet received from a subscriber (the
inside local address) to another (the inside global address) before forwarding the packet to the WAN
side. When the response comes back, NAT translates the destination address (the inside global address)
back to the inside local address before forwarding it to the original inside host.
Port Forwarding
A port forwarding set is a list of inside (behind NAT on the LAN) servers, for example, web or FTP, that you
can make visible to the outside world even though NAT makes your whole inside network appear as a
single computer to the outside world.
Finding Out More
See Section 11.9 on page 175 for advanced technical information on NAT.
11.2 The Port Forwarding Screen
Use the Port Forwarding screen to forward incoming service requests to the server(s) on your local
network.
You may enter a single port number or a range of port numbers to be forwarded, and the local IP
address of the desired server. The port number identifies a service; for example, web service is on port 80
and FTP on port 21. In some cases, such as for unknown services or where one server can support more
than one service (for example both FTP and web service), it might be better to specify a range of port
numbers. You can allocate a server IP address that corresponds to a port or a range of ports.
The most often used port numbers and services are shown in Appendix D on page 287. Please refer to
RFC 1700 for further information about port numbers.
Note: Many residential broadband ISP accounts do not allow you to run any server processes
(such as a Web or FTP server) from your location. Your ISP may periodically check for
servers and may suspend your account if it discovers any active services at your
location. If you are unsure, refer to your ISP.
Configuring Servers Behind Port Forwarding (Example)
Let's say you want to assign ports 21-25 to one FTP, Telnet and SMTP server (A in the example), port 80 to
another (B in the example) and assign a default server IP address of 192.168.1.35 to a third (C in the
example). You assign the LAN IP addresses and the ISP assigns the WAN IP address. The NAT network
appears as a single host on the Internet.
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Figure 79 Multiple Servers Behind NAT Example
Click Network Setting > NAT > Port Forwarding to open the following screen.
See Appendix D on page 287 for port numbers commonly used for particular services.
Figure 80 Network Setting > NAT > Port Forwarding
The following table describes the fields in this screen.
Table 56 Network Setting > NAT > Port Forwarding
LABEL DESCRIPTION
Add New Rule Click this to add a new rule.
#This is the index number of the entry.
Status This field displays whether the NAT rule is active or not. A yellow bulb signifies that this rule is
active. A gray bulb signifies that this rule is not active.
Service Name This shows the service’s name.
WAN Interface This shows the WAN interface through which the service is forwarded.
Server IP
Address
This is the server’s IP address.
Start Port This is the first external port number that identifies a service.
End Port This is the last external port number that identifies a service.
Translation Start
Port
This is the first internal port number that identifies a service.
Translation End
Port
This is the last internal port number that identifies a service.
Protocol This shows the IP protocol supported by this virtual server, whether it is TCP, UDP, or TCP/UDP.
Modify Click the Edit icon to edit this rule.
Click the Delete icon to delete an existing rule.
DSL
IP Address assigned by ISP
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11.2.1 Add/Edit Port Forwarding
Click Add New Rule in the Port Forwarding screen or click the Edit icon next to an existing rule to open
the following screen.
Figure 81 Port Forwarding: Add/Edit
The following table describes the labels in this screen.
Table 57 Port Forwarding: Add/Edit
LABEL DESCRIPTION
Active Select Enable or Disable to activate or deactivate the rule.
Service Name Enter a name to identify this rule using keyboard characters (A-Z, a-z, 1-2 and so on).
WAN Interface Select the WAN interface through which the service is forwarded.
You must have already configured a WAN connection with NAT enabled.
Start Port Enter the original destination port for the packets.
To forward only one port, enter the port number again in the End Port field.
To forward a series of ports, enter the start port number here and the end port number in the End
Port field.
End Port Enter the last port of the original destination port range.
To forward only one port, enter the port number in the Start Port field above and then enter it
again in this field.
To forward a series of ports, enter the last port number in a series that begins with the port
number in the Start Port field above.
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11.3 The Applications Screen
This screen provides a summary of all NAT applications and their configuration. In addition, this screen
allows you to create new applications and/or remove existing ones.
To access this screen, click Network Setting > NAT > Applications. The following screen appears.
Figure 82 Network Setting > NAT > Applications
The following table describes the labels in this screen.
Translation Start
Port
This shows the port number to which you want the VMG to translate the incoming port. For a
range of ports, enter the first number of the range to which you want the incoming ports
translated.
Translation End
Port
This shows the last port of the translated port range.
Server IP
Address
Enter the inside IP address of the virtual server here.
Protocol Select the protocol supported by this virtual server. Choices are TCP, UDP, or TCP/UDP.
Wake up this
target by Wake
On Lan(WOL)
Select this to turn on the virtual server remotely.
MAC address of
WOL device
Enter the MAC address of the device to turn it on.
OK Click OK to save your changes.
Cancel Click Cancel to exit this screen without saving.
Table 57 Port Forwarding: Add/Edit (continued)
LABEL DESCRIPTION
Table 58 Network Setting > NAT > Applications
LABEL DESCRIPTION
Add New
Application
Click this to add a new NAT application rule.
#This is the index number of the entry.
Application
Forwarded
This field shows the type of application that the service forwards.
WAN Interface This field shows the WAN interface through which the service is forwarded.
Server IP
Address
This field displays the destination IP address for the service.
Modify Click the Delete icon to delete the rule.
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11.3.1 Add New Application
This screen lets you create new NAT application rules. Click Add New Application in the Applications
screen to open the following screen.
Figure 83 Applications: Add
The following table describes the labels in this screen.
11.4 The Port Triggering Screen
Some services use a dedicated range of ports on the client side and a dedicated range of ports on the
server side. With regular port forwarding you set a forwarding port in NAT to forward a service (coming in
from the server on the WAN) to the IP address of a computer on the client side (LAN). The problem is that
port forwarding only forwards a service to a single LAN IP address. In order to use the same service on a
different LAN computer, you have to manually replace the LAN computer's IP address in the forwarding
port with another LAN computer's IP address.
Trigger port forwarding solves this problem by allowing computers on the LAN to dynamically take turns
using the service. The VMG records the IP address of a LAN computer that sends traffic to the WAN to
Table 59 Applications: Add
LABEL DESCRIPTION
WAN Interface Select the WAN interface that you want to apply this NAT rule to.
Server IP
Address
Enter the inside IP address of the application here.
Application
Category
Select the category of the application from the drop-down list box.
Application
Forwarded
Select a service from the drop-down list box and the VMG automatically configures the
protocol, start, end, and map port number that define the service.
View Rules Click this to display the configuration of the service that you have chosen in Application
Fowarded.
OK Click OK to save your changes.
Cancel Click Cancel to exit this screen without saving.
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request a service with a specific port number and protocol (a "trigger" port). When the VMG's WAN port
receives a response with a specific port number and protocol ("open" port), the VMG forwards the
traffic to the LAN IP address of the computer that sent the request. After that computer’s connection for
that service closes, another computer on the LAN can use the service in the same manner. This way you
do not need to configure a new IP address each time you want a different LAN computer to use the
application.
For example:
Figure 84 Trigger Port Forwarding Process: Example
1Jane requests a file from the Real Audio server (port 7070).
2Port 7070 is a “trigger” port and causes the VMG to record Jane’s computer IP address. The VMG
associates Jane's computer IP address with the "open" port range of 6970-7170.
3The Real Audio server responds using a port number ranging between 6970-7170.
4The VMG forwards the traffic to Jane’s computer IP address.
5Only Jane can connect to the Real Audio server until the connection is closed or times out. The VMG
times out in three minutes with UDP (User Datagram Protocol) or two hours with TCP/IP (Transfer Control
Protocol/Internet Protocol).
Click Network Setting > NAT > Port Triggering to open the following screen. Use this screen to view your
VMG’s trigger port settings.
Figure 85 Network Setting > NAT > Port Triggering
DSL
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The following table describes the labels in this screen.
11.4.1 Add/Edit Port Triggering Rule
This screen lets you create new port triggering rules. Click Add new rule in the Port Triggering screen or
click a rule’s Edit icon to open the following screen.
Figure 86 Port Triggering: Add/Edit
Table 60 Network Setting > NAT > Port Triggering
LABEL DESCRIPTION
Add New Rule Click this to create a new rule.
#This is the index number of the entry.
Status This field displays whether the port triggering rule is active or not. A yellow bulb signifies that this
rule is active. A gray bulb signifies that this rule is not active.
Service Name This field displays the name of the service used by this rule.
WAN Interface This field shows the WAN interface through which the service is forwarded.
Trigger Start Port The trigger port is a port (or a range of ports) that causes (or triggers) the VMG to record the IP
address of the LAN computer that sent the traffic to a server on the WAN.
This is the first port number that identifies a service.
Trigger End Port This is the last port number that identifies a service.
Trigger Proto. This is the trigger transport layer protocol.
Open Start Port The open port is a port (or a range of ports) that a server on the WAN uses when it sends out a
particular service. The VMG forwards the traffic with this port (or range of ports) to the client
computer on the LAN that requested the service.
This is the first port number that identifies a service.
Open End Port This is the last port number that identifies a service.
Open Proto. This is the open transport layer protocol.
Modify Click the Edit icon to edit this rule.
Click the Delete icon to delete an existing rule.
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The following table describes the labels in this screen.
11.5 The DMZ Screen
In addition to the servers for specified services, NAT supports a default server IP address. A default server
receives packets from ports that are not specified in the NAT Port Forwarding Setup screen.
Figure 87 Network Setting > NAT > DMZ
The following table describes the fields in this screen.
Table 61 Port Triggering: Configuration Add/Edit
LABEL DESCRIPTION
Active Select Enable or Disable to activate or deactivate the rule.
Service Name Enter a name to identify this rule using keyboard characters (A-Z, a-z, 1-2 and so on).
WAN Interface Select a WAN interface for which you want to configure port triggering rules.
Trigger Start Port The trigger port is a port (or a range of ports) that causes (or triggers) the VMG to record the IP
address of the LAN computer that sent the traffic to a server on the WAN.
Type a port number or the starting port number in a range of port numbers.
Trigger End Port Type a port number or the ending port number in a range of port numbers.
Trigger Protocol Select the transport layer protocol from TCP or UDP.
Open Start Port The open port is a port (or a range of ports) that a server on the WAN uses when it sends out a
particular service. The VMG forwards the traffic with this port (or range of ports) to the client
computer on the LAN that requested the service.
Type a port number or the starting port number in a range of port numbers.
Open End Port Type a port number or the ending port number in a range of port numbers.
Open Protocol Select the transport layer protocol from TCP or UDP.
OK Click OK to save your changes.
Cancel Click Cancel to exit this screen without saving.
Table 62 Network Setting > NAT > DMZ
LABEL DESCRIPTION
Default Server
Address
Enter the IP address of the default server which receives packets from ports that are not
specified in the NAT Port Forwarding screen.
Note: If you do not assign a Default Server Address, the VMG discards all packets
received for ports that are not specified in the NAT Port Forwarding screen.
Apply Click Apply to save your changes.
Cancel Click Cancel to restore your previously saved settings.
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11.6 The ALG Screen
Some NAT routers may include a SIP Application Layer Gateway (ALG). A SIP ALG allows SIP calls to pass
through NAT by examining and translating IP addresses embedded in the data stream. When the VMG
registers with the SIP register server, the SIP ALG translates the VMG’s private IP address inside the SIP
data stream to a public IP address. You do not need to use STUN or an outbound proxy if your VMG is
behind a SIP ALG.
Use this screen to enable and disable the ALGs in the VMG. To access this screen, click Network Setting
> NAT > ALG.
Figure 88 Network Setting > NAT > ALG
The following table describes the fields in this screen.
11.7 The Address Mapping Screen
Ordering your rules is important because the VMG applies the rules in the order that you specify. When a
rule matches the current packet, the VMG takes the corresponding action and the remaining rules are
ignored.
Click Network Setting > NAT > Address Mapping to display the following screen.
Table 63 Network Setting > NAT > ALG
LABEL DESCRIPTION
NAT ALG Enable this to make sure applications such as FTP and file transfer in IM applications work
correctly with port-forwarding and address-mapping rules.
SIP ALG Enable this to make sure SIP (VoIP) works correctly with port-forwarding and address-mapping
rules.
RTSP ALG Enable this to have the VMG detect RTSP traffic and help build RTSP sessions through its NAT. The
Real Time Streaming (media control) Protocol (RTSP) is a remote control for multimedia on the
Internet.
PPTP ALG Enable this to turn on the PPTP ALG on the VMG to detect PPTP traffic and help build PPTP
sessions through the VMG’s NAT.
IPSEC ALG Enable this to turn on the IPsec ALG on the VMG to detect IPsec traffic and help build IPsec
sessions through the VMG’s NAT.
Apply Click Apply to save your changes.
Cancel Click Cancel to restore your previously saved settings.
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Figure 89 Network Setting > NAT > Address Mapping
The following table describes the fields in this screen.
11.7.1 Add/Edit Address Mapping Rule
To add or edit an address mapping rule, click Add new rule or the rule’s edit icon in the Address
Mapping screen to display the screen shown next.
Table 64 Network Setting > NAT > Address Mapping
LABEL DESCRIPTION
Add new rule Click this to create a new rule.
Rule Name This is the name of the rule.
Local Start IP This is the starting Inside Local IP Address (ILA).
Local End IP This is the ending Inside Local IP Address (ILA). If the rule is for all local IP addresses, then this field
displays 0.0.0.0 as the Local Start IP address and 255.255.255.255 as the Local End IP address. This
field is blank for One-to-One mapping types.
Global Start IP This is the starting Inside Global IP Address (IGA). Enter 0.0.0.0 here if you have a dynamic IP
address from your ISP. You can only do this for the Many-to-One mapping type.
Global End IP This is the ending Inside Global IP Address (IGA). This field is blank for One-to-One and Many-to-
One mapping types.
Type This is the address mapping type.
One-to-One: This mode maps one local IP address to one global IP address. Note that port
numbers do not change for the One-to-one NAT mapping type.
Many-to-One: This mode maps multiple local IP addresses to one global IP address. This is
equivalent to SUA (i.e., PAT, port address translation), the VMG's Single User Account feature that
previous routers supported only.
Many-to-Many: This mode maps multiple local IP addresses to shared global IP addresses.
Wan Interface This is the WAN interface to which the address mapping rule applies.
Modify Click the Edit icon to go to the screen where you can edit the address mapping rule.
Click the Delete icon to delete an existing address mapping rule. Note that subsequent address
mapping rules move up by one when you take this action.
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Figure 90 Address Mapping: Add/Edit
The following table describes the fields in this screen.
11.8 The Sessions Screen
Use this screen to limit the number of concurrent NAT sessions a client can use. Click Network Setting >
NAT > Sessions to display the following screen.
Table 65 Address Mapping: Add/Edit
LABEL DESCRIPTION
Rule Name Type up to 20 alphanumberic characters for the name of this rule.
Type Choose the IP/port mapping type from one of the following.
One-to-One: This mode maps one local IP address to one global IP address. Note that port
numbers do not change for the One-to-one NAT mapping type.
Many-to-One: This mode maps multiple local IP addresses to one global IP address. This is
equivalent to SUA (i.e., PAT, port address translation), the VMG's Single User Account feature that
previous routers supported only.
Many-to-Many: This mode maps multiple local IP addresses to shared global IP addresses.
Local Start IP Enter the starting Inside Local IP Address (ILA).
Local End IP Enter the ending Inside Local IP Address (ILA). If the rule is for all local IP addresses, then this field
displays 0.0.0.0 as the Local Start IP address and 255.255.255.255 as the Local End IP address. This
field is blank for One-to-One mapping types.
Global Start IP Enter the starting Inside Global IP Address (IGA). Enter 0.0.0.0 here if you have a dynamic IP
address from your ISP. You can only do this for the Many-to-One mapping type.
Global End IP Enter the ending Inside Global IP Address (IGA). This field is blank for One-to-One and Many-to-
One mapping types.
WAN Interface Select a WAN interface to which the address mapping rule applies.
OK Click OK to save your changes.
Cancel Click Cancel to exit this screen without saving.
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Figure 91 Network Setting > NAT > Sessions
The following table describes the fields in this screen.
11.9 Technical Reference
This part contains more information regarding NAT.
11.9.1 NAT Definitions
Inside/outside denotes where a host is located relative to the VMG, for example, the computers of your
subscribers are the inside hosts, while the web servers on the Internet are the outside hosts.
Global/local denotes the IP address of a host in a packet as the packet traverses a router, for example,
the local address refers to the IP address of a host when the packet is in the local network, while the
global address refers to the IP address of the host when the same packet is traveling in the WAN side.
Note that inside/outside refers to the location of a host, while global/local refers to the IP address of a
host used in a packet. Thus, an inside local address (ILA) is the IP address of an inside host in a packet
when the packet is still in the local network, while an inside global address (IGA) is the IP address of the
same inside host when the packet is on the WAN side. The following table summarizes this information.
NAT never changes the IP address (either local or global) of an outside host.
Table 66 Network Setting > NAT > Sessions
LABEL DESCRIPTION
MAX NAT
Session Per Host
(0 ~ 20480)
Use this field to set a limit to the number of concurrent NAT sessions each client host can have.
If only a few clients use peer to peer applications, you can raise this number to improve their
performance. With heavy peer-to-peer application use, lower this number to ensure no single
client uses too many of the available NAT sessions.
Apply Click this to save your changes on this screen.
Cancel Click this to exit this screen without saving any changes.
Table 67 NAT Definitions
ITEM DESCRIPTION
Inside This refers to the host on the LAN.
Outside This refers to the host on the WAN.
Local This refers to the packet address (source or destination) as the packet travels on the LAN.
Global This refers to the packet address (source or destination) as the packet travels on the WAN.
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11.9.2 What NAT Does
In the simplest form, NAT changes the source IP address in a packet received from a subscriber (the
inside local address) to another (the inside global address) before forwarding the packet to the WAN
side. When the response comes back, NAT translates the destination address (the inside global address)
back to the inside local address before forwarding it to the original inside host. Note that the IP address
(either local or global) of an outside host is never changed.
The global IP addresses for the inside hosts can be either static or dynamically assigned by the ISP. In
addition, you can designate servers, for example, a web server and a telnet server, on your local
network and make them accessible to the outside world. If you do not define any servers (for Many-to-
One and Many-to-Many Overload mapping), NAT offers the additional benefit of firewall protection.
With no servers defined, your VMG filters out all incoming inquiries, thus preventing intruders from probing
your network. For more information on IP address translation, refer to RFC 1631, The IP Network Address
Translator (NAT).
11.9.3 How NAT Works
Each packet has two addresses – a source address and a destination address. For outgoing packets,
the ILA (Inside Local Address) is the source address on the LAN, and the IGA (Inside Global Address) is
the source address on the WAN. For incoming packets, the ILA is the destination address on the LAN,
and the IGA is the destination address on the WAN. NAT maps private (local) IP addresses to globally
unique ones required for communication with hosts on other networks. It replaces the original IP source
address (and TCP or UDP source port numbers for Many-to-One and Many-to-Many Overload NAT
mapping) in each packet and then forwards it to the Internet. The VMG keeps track of the original
addresses and port numbers so incoming reply packets can have their original values restored. The
following figure illustrates this.
Figure 92 How NAT Works
11.9.4 NAT Application
The following figure illustrates a possible NAT application, where three inside LANs (logical LANs using IP
alias) behind the VMG can communicate with three distinct WAN networks.
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Figure 93 NAT Application With IP Alias
Port Forwarding: Services and Port Numbers
The most often used port numbers are shown in the following table. Please refer to RFC 1700 for further
information about port numbers. Please also refer to the Supporting CD for more examples and details
on port forwarding and NAT.
Table 68 Services and Port Numbers
SERVICES PORT NUMBER
ECHO 7
FTP (File Transfer Protocol) 21
SMTP (Simple Mail Transfer Protocol) 25
DNS (Domain Name System) 53
Finger 79
HTTP (Hyper Text Transfer protocol or WWW, Web) 80
POP3 (Post Office Protocol) 110
NNTP (Network News Transport Protocol) 119
SNMP (Simple Network Management Protocol) 161
SNMP trap 162
PPTP (Point-to-Point Tunneling Protocol) 1723
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Port Forwarding Example
Let's say you want to assign ports 21-25 to one FTP, Telnet and SMTP server (A in the example), port 80 to
another (B in the example) and assign a default server IP address of 192.168.1.35 to a third (C in the
example). You assign the LAN IP addresses and the ISP assigns the WAN IP address. The NAT network
appears as a single host on the Internet.
Figure 94 Multiple Servers Behind NAT Example
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CHAPTER 12
Dynamic DNS Setup
12.1 Overview
DNS
DNS (Domain Name System) is for mapping a domain name to its corresponding IP address and vice
versa. The DNS server is extremely important because without it, you must know the IP address of a
machine before you can access it.
In addition to the system DNS server(s), each WAN interface (service) is set to have its own static or
dynamic DNS server list. You can configure a DNS static route to forward DNS queries for certain domain
names through a specific WAN interface to its DNS server(s). The VMG uses a system DNS server (in the
order you specify in the Broadband screen) to resolve domain names that do not match any DNS
routing entry. After the VMG receives a DNS reply from a DNS server, it creates a new entry for the
resolved IP address in the routing table.
Dynamic DNS
Dynamic DNS allows you to update your current dynamic IP address with one or many dynamic DNS
services so that anyone can contact you (in NetMeeting, CU-SeeMe, etc.). You can also access your
FTP server or Web site on your own computer using a domain name (for instance myhost.dhs.org, where
myhost is a name of your choice) that will never change instead of using an IP address that changes
each time you reconnect. Your friends or relatives will always be able to call you even if they don't know
your IP address.
First of all, you need to have registered a dynamic DNS account with www.dyndns.org. This is for people
with a dynamic IP from their ISP or DHCP server that would still like to have a domain name. The Dynamic
DNS service provider will give you a password or key.
12.1.1 What You Can Do in this Chapter
• Use the DNS Entry screen to view, configure, or remove DNS routes (Section 12.2 on page 180).
• Use the Dynamic DNS screen to enable DDNS and configure the DDNS settings on the VMG (Section
12.3 on page 181).
12.1.2 What You Need To Know
DYNDNS Wildcard
Enabling the wildcard feature for your host causes *.yourhost.dyndns.org to be aliased to the same IP
address as yourhost.dyndns.org. This feature is useful if you want to be able to use, for example,
www.yourhost.dyndns.org and still reach your hostname.
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If you have a private WAN IP address, then you cannot use Dynamic DNS.
12.2 The DNS Entry Screen
Use this screen to view and configure DNS routes on the VMG. Click Network Setting > DNS to open the
DNS Entry screen.
Figure 95 Network Setting > DNS > DNS Entry
The following table describes the fields in this screen.
12.2.1 Add/Edit DNS Entry
You can manually add or edit the VMG’s DNS name and IP address entry. Click Add New DNS Entry in
the DNS Entry screen or the Edit icon next to the entry you want to edit. The screen shown next appears.
Figure 96 DNS Entry: Add/Edit
Table 69 Network Setting > DNS > DNS Entry
LABEL DESCRIPTION
Add New DNS
Entry
Click this to create a new DNS entry.
#This is the index number of the entry.
Hostname This indicates the host name or domain name.
IP Address This indicates the IP address assigned to this computer.
Modify Click the Edit icon to edit the rule.
Click the Delete icon to delete an existing rule.
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The following table describes the labels in this screen.
12.3 The Dynamic DNS Screen
Use this screen to change your VMG’s DDNS. Click Network Setting > DNS > Dynamic DNS. The screen
appears as shown.
Figure 97 Network Setting > DNS > Dynamic DNS
The following table describes the fields in this screen.
Table 70 DNS Entry: Add/Edit
LABEL DESCRIPTION
Host Name Enter the host name of the DNS entry.
IP Address Enter the IP address of the DNS entry.
OK Click OK to save your changes.
Cancel Click Cancel to exit this screen without saving.
Table 71 Network Setting > DNS > > Dynamic DNS
LABEL DESCRIPTION
Dynamic DNS Setup
Dynamic DNS Select Enable to use dynamic DNS.
Service Provider Select your Dynamic DNS service provider from the drop-down list box.
Host Name Type the domain name assigned to your VMG by your Dynamic DNS provider.
You can specify up to two host names in the field separated by a comma (",").
Username Type your user name.
Password Type the password assigned to you.
Dynamic DNS Status
User
Authentication
Result
This shows Success if the account is correctly set up with the Dynamic DNS provider
account.
Last Updated Time This shows the last time the IP address the Dynamic DNS provider has associated with the
hostname was updated.
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Current Dynamic
IP This shows the IP address your Dynamic DNS provider has currently associated with the
hostname.
Apply Click Apply to save your changes.
Cancel Click Cancel to exit this screen without saving.
Table 71 Network Setting > DNS > > Dynamic DNS (continued)
LABEL DESCRIPTION
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CHAPTER 13
Interface Grouping
13.1 Overview
By default, all LAN and WAN interfaces on the VMG are in the same group and can communicate with
each other. Create interface groups to have the VMG assign the IP addresses in different domains to
different groups. Each group acts as an independent network on the VMG. This lets devices connected
to an interface group’s LAN interfaces communicate through the interface group’s WAN or LAN
interfaces but not other WAN or LAN interfaces.
13.1.1 What You Can Do in this Chapter
The Interface Grouping screens let you create multiple networks on the VMG (Section 13.2 on page
183).
13.2 The Interface Group Screen
You can manually add a LAN interface to a new group. Alternatively, you can have the VMG
automatically add the incoming traffic and the LAN interface on which traffic is received to an
interface group when its DHCP Vendor ID option information matches one listed for the interface group.
Use the LAN screen to configure the private IP addresses the DHCP server on the VMG assigns to the
clients in the default and/or user-defined groups. If you set the VMG to assign IP addresses based on the
client’s DHCP Vendor ID option information, you must enable DHCP server and configure LAN TCP/IP
settings for both the default and user-defined groups. See Chapter 8 on page 123 for more information.
In the following example, the client that sends packets with the DHCP Vendor ID option set to MSFT 5.0
(meaning it is a Windows 2000 DHCP client) is assigned the IP address 192.168.2.2 and uses the WAN
VDSL_PoE/ppp0.1 interface.
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Figure 98 Interface Grouping Application
Click Network Setting > Interface Grouping to open the following screen.
Figure 99 Network Setting > Interface Grouping
The following table describes the fields in this screen.
13.2.1 Interface Group Configuration
Click the Add New Interface Group button in the Interface Grouping screen to open the following
screen. Use this screen to create a new interface group.
Note: An interface can belong to only one group at a time.
Table 72 Network Setting > Interface Grouping
LABEL DESCRIPTION
Add New
Interface Group
Click this button to create a new interface group.
Group Name This shows the descriptive name of the group.
WAN Interface This shows the WAN interfaces in the group.
LAN Interfaces This shows the LAN interfaces in the group.
Criteria This shows the filtering criteria for the group.
Modify Click the Delete icon to remove the group.
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Figure 100 Interface Group Configuration
The following table describes the fields in this screen.
Table 73 Interface Group Configuration
LABEL DESCRIPTION
Group Name Enter a name to identify this group. You can enter up to 30 characters. You can use letters,
numbers, hyphens (-) and underscores (_). Spaces are not allowed.
WAN Interface
used in the
grouping
Select the WAN interface this group uses. The group can have up to one PTM interface, up to
one ATM interface, up to one ETH interface, and up to one WWAN interface.
Selected LAN
Interfaces
Available LAN
Interfaces
Select one or more LAN interfaces (Ethernet LAN, HPNA or wireless LAN) in the Selected LAN
Interfaces list and use the left arrow to move them to the Available LAN Interfaces list to add the
interfaces to this group.
To remove a LAN or wireless LAN interface from the Available LAN Interfaces, use the right-
facing arrow.
Automatically
Add Clients With
the following
DHCP Vendor
IDs
Click Add to identify LAN hosts to add to the interface group by criteria such as the type of the
hardware or firmware. See Section 13.2.2 on page 186 for more information.
#This shows the index number of the rule.
Filter Criteria This shows the filtering criteria. The LAN interface on which the matched traffic is received will
belong to this group automatically.
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13.2.2 Interface Grouping Criteria
Click the Add button in the Interface Grouping Configuration screen to open the following screen.
Figure 101 Interface Grouping Criteria
The following table describes the fields in this screen.
WildCard
Support
This shows if wildcard on DHCP option 60 is enabled.
Modify Click the Edit icon to change the group setting
Click the Delete icon to delete this group from the VMG.
OK Click OK to save your changes.
Cancel Click Cancel to exit this screen without saving.
Table 73 Interface Group Configuration (continued)
LABEL DESCRIPTION
Table 74 Interface Grouping Criteria
LABEL DESCRIPTION
Source MAC
Address
Select this option and enter the source MAC address of the packet.
DHCP Option 60 Select this option and enter the Vendor Class Identifier (Option 60) of the matched traffic, such
as the type of the hardware or firmware.
Enable
wildcard Select this option to be able to use wildcards in the Vendor Class Identifier configured for DHCP
option 60.
DHCP Option 61 Select this and enter the device identity of the matched traffic.
Enter the Identity Association Identifier (IAID) of the device, for example, the WAN connection
index number.
DHCP Option
125
Select this and enter vendor specific information of the matched traffic.
Enterprise
Number Enter the vendor’s 32-bit enterprise number registered with the IANA (Internet Assigned Numbers
Authority).
Manufactur
er OUI Specify the vendor’s OUI (Organization Unique Identifier). It is usually the first three bytes of the
MAC address.
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Serial
Number Enter the serial number of the device.
Product
Class Enter the product class of the device.
OK Click OK to save your changes.
Cancel Click Cancel to exit this screen without saving.
Table 74 Interface Grouping Criteria (continued)
LABEL DESCRIPTION
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CHAPTER 14
USB Service
14.1 Overview
You can share files on a USB memory stick or hard drive connected to your VMG with users on your
network.
The following figure is an overview of the VMG’s file server feature. Computers A and B can access files
on a USB device (C) which is connected to the VMG.
Figure 102 File Sharing Overview
The VMG will not be able to join the workgroup if your local area network has restrictions set up
that do not allow devices to join a workgroup. In this case, contact your network administrator.
14.1.1 What You Can Do in this Chapter
• Use the File Sharing screen to enable file-sharing server (Section 14.1.3 on page 189).
• Use the Media Server screen to enable or disable the sharing of media files (Section 14.3 on page
192).
14.1.2 What You Need To Know
The following terms and concepts may help as you read this chapter.
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14.1.2.1 About File Sharing
Workgroup name
This is the name given to a set of computers that are connected on a network and share resources such
as a printer or files. Windows automatically assigns the workgroup name when you set up a network.
Shares
When settings are set to default, each USB device connected to the VMG is given a folder, called a
“share”. If a USB hard drive connected to the VMG has more than one partition, then each partition will
be allocated a share. You can also configure a “share” to be a sub-folder or file on the USB device.
File Systems
A file system is a way of storing and organizing files on your hard drive and storage device. Often
different operating systems such as Windows or Linux have different file systems. The file sharing feature
on your VMG supports File Allocation Table (FAT) and FAT32.
Common Internet File System
The VMG uses Common Internet File System (CIFS) protocol for its file sharing functions. CIFS compatible
computers can access the USB file storage devices connected to the VMG. CIFS protocol is supported
on Microsoft Windows, Linux Samba and other operating systems (refer to your systems specifications for
CIFS compatibility).
14.1.3 Before You Begin
Make sure the VMG is connected to your network and turned on.
1Connect the USB device to one of the VMG’s USB port. Make sure the VMG is connected to your
network.
2The VMG detects the USB device and makes its contents available for browsing. If you are connecting a
USB hard drive that comes with an external power supply, make sure it is connected to an appropriate
power source that is on.
Note: If your USB device cannot be detected by the VMG, see the troubleshooting for
suggestions.
14.2 The File Sharing Screen
Use this screen to set up file sharing through the VMG. The VMG’s LAN users can access the shared
folder (or share) from the USB device inserted in the VMG. To access this screen, click Network Setting >
USB Service > File Sharing.
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Figure 103 Network Setting > USB Service > File Sharing
Note: Share Directory List field appears when you connect a USB device to the USB port.
Otherwise, it doesn’t.
Each field is described in the following table.
Table 75 Network Setting > USB Service > File Sharing
LABEL DESCRIPTION
Information
Volume This is the volume name the VMG gives to an inserted USB device.
Capacity This is the total available memory size (in megabytes) on the USB device.
Used Space This is the memory size (in megabytes) already used on the USB device.
Server Configuration
File Sharing
Services
Select Enable to activate file sharing through the VMG.
Share Directory List
Add New Share Click this to set up a new share on the VMG.
Active Select this to allow the share to be accessed.
Status This field shows the status of the share
: The share is not activated.
: The share is activated.
Share Name This field displays the share name on the GPON Device.
Share Path This field displays the path for the share directories (folders) on the GPON Device. These are the
directories (folders) on your USB storage device.
Share
Description
This field displays information about the share.
Modify Click the Edit icon to change the settings of an existing share.
Click the Delete icon to delete this share in the list.
Account Management
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14.2.1 The Add New Share Screen
Use this screen to set up a new share or edit an existing share on the VMG. Click Add new share in the
File Sharing screen or click the Edit icon next to an existing share.
Please note that you need to set up your shares in the USB before enabling file sharing in the VMG. Also,
the following special characters are not allowed for the USB share name: ", ', `, <, >, ^, $, |, &, ;, \, /, :, *,
and ?.
Figure 104 Network Setting > USB Service > File Sharing > Add New Sharer
The following table describes the labels in this menu.
Add New User Click this button to create a user account to access the secured shares.
Status This field shows the status of the user.
: The user account is not activated for the share.
: The user account is activated for the share.
User Name This is the name of a user who is allowed to access the secured shares on the USB device.
Apply Click this to save your changes to the VMG.
Cancel Click this to restore your previously saved settings.
Table 75 Network Setting > USB Service > File Sharing
LABEL DESCRIPTION
Table 76 Network Setting > USB Service > Media Server
LABEL DESCRIPTION
Volume Select the volume in the USB storage device that you want to add as a share in the VMG.
This field is read-only when you are editing the share.
Share Path Manually enter the file path for the share, or click the Browse button and select the folder that
you want to add as a share.
This field is read-only when you are editing the share.
Description You can either enter a short description of the share, or leave this field blank.
Access Level Select Public if you want the share to be accessed by users connecting to the VMG. Otherwise,
select Security.
Apply Click Apply to save your changes.
Cancel Click Back to return to the previous screen.
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14.2.2 The Add New User Screen
Once you click the Add New User button, you’ll be directed to the User Account screen. To create a
user account that can access the secured shares on the USB device, click the Add New Account button
in the Network Setting > Maintenance > User Account screen.
Please see Chapter 27 on page 231, for detailed information about User Account screen.
14.3 The Media Server Screen
The media server feature lets anyone on your network play video, music, and photos from the USB
storage device connected to your VMG (without having to copy them to another computer). The VMG
can function as a DLNA-compliant media server. The VMG streams files to DLNA-compliant media
clients (like Windows Media Player). The Digital Living Network Alliance (DLNA) is a group of personal
computer and electronics companies that works to make products compatible in a home network.
The VMG media server enables you to:
• Publish all shares for everyone to play media files in the USB storage device connected to the VMG.
• Use hardware-based media clients like the DMA-2500 to play the files.
Note: Anyone on your network can play the media files in the published shares. No user name
and password or other form of security is used. The media server is enabled by default
with the video, photo, and music shares published.
To change your VMG’s media server settings, click Network Setting > USB Service > Media Server. The
screen appears as shown.
Figure 105 Network Setting > USB Service > Media Server
The following table describes the labels in this menu.
Table 77 Network Setting > USB Service > Media Server
LABEL DESCRIPTION
Media Server Select Enable to have the VMG function as a DLNA-compliant media server.
Enable the media server to let (DLNA-compliant) media clients on your network play media files
located in the shares.
Interface Select an interface on which you want to enable the media server function.
Media Library
Path
Enter the path clients use to access the media files on a USB storage device connected to the
VMG.
Apply Click Apply to save your changes.
Cancel Click Cancel to restore your previously saved settings.
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CHAPTER 15
Firewall
15.1 Overview
This chapter shows you how to enable and configure the VMG’s security settings. Use the firewall to
protect your VMG and network from attacks by hackers on the Internet and control access to it. By
default the firewall:
• allows traffic that originates from your LAN computers to go to all other networks.
• blocks traffic that originates on other networks from going to the LAN.
The following figure illustrates the default firewall action. User A can initiate an IM (Instant Messaging)
session from the LAN to the WAN (1). Return traffic for this session is also allowed (2). However other traffic
initiated from the WAN is blocked (3 and 4).
Figure 106 Default Firewall Action
15.1.1 What You Can Do in this Chapter
• Use the General screen to configure the security level of the firewall on the VMG (Section 15.2 on
page 194).
• Use the Protocol screen to add or remove predefined Internet services and configure firewall rules
(Section 15.3 on page 195).
• Use the Access Control screen to view and configure incoming/outgoing filtering rules (Section 15.4
on page 197).
• Use the DoS screen to activate protection against Denial of Service (DoS) attacks (Section 15.5 on
page 199).
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15.1.2 What You Need to Know
SYN Attack
A SYN attack floods a targeted system with a series of SYN packets. Each packet causes the targeted
system to issue a SYN-ACK response. While the targeted system waits for the ACK that follows the SYN-
ACK, it queues up all outstanding SYN-ACK responses on a backlog queue. SYN-ACKs are moved off the
queue only when an ACK comes back or when an internal timer terminates the three-way handshake.
Once the queue is full, the system will ignore all incoming SYN requests, making the system unavailable
for legitimate users.
DoS
Denials of Service (DoS) attacks are aimed at devices and networks with a connection to the Internet.
Their goal is not to steal information, but to disable a device or network so users no longer have access
to network resources. The VMG is pre-configured to automatically detect and thwart all known DoS
attacks.
DDoS
A DDoS attack is one in which multiple compromised systems attack a single target, thereby causing
denial of service for users of the targeted system.
LAND Attack
In a LAND attack, hackers flood SYN packets into the network with a spoofed source IP address of the
target system. This makes it appear as if the host computer sent the packets to itself, making the system
unavailable while the target system tries to respond to itself.
Ping of Death
Ping of Death uses a "ping" utility to create and send an IP packet that exceeds the maximum 65,536
bytes of data allowed by the IP specification. This may cause systems to crash, hang or reboot.
SPI
Stateful Packet Inspection (SPI) tracks each connection crossing the firewall and makes sure it is valid.
Filtering decisions are based not only on rules but also context. For example, traffic from the WAN may
only be allowed to cross the firewall in response to a request from the LAN.
15.2 The Firewall Screen
Use this screen to set the security level of the firewall on the VMG. Firewall rules are grouped based on
the direction of travel of packets to which they apply.
Click Security > Firewall to display the General screen.
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Figure 107 Security > Firewall > General
The following table describes the labels in this screen.
15.3 The Protocol Screen
You can configure customized services and port numbers in the Protocol screen. For a comprehensive
list of port numbers and services, visit the IANA (Internet Assigned Number Authority) website. See
Appendix D on page 287 for some examples.
Click Security > Firewall > Protocol to display the following screen.
Figure 108 Security > Firewall > Protocol
Table 78 Security > Firewall > General
LABEL DESCRIPTION
Firewall Select Enable to activate the firewall feature on the VMG.
Low Select Low to allow LAN to WAN and WAN to LAN packet directions.
Medium Select Medi u m to allow LAN to WAN but deny WAN to LAN packet directions.
High Select High to deny LAN to WAN and WAN to LAN packet directions.
Apply Click Apply to save your changes.
Cancel Click Cancel to restore your previously saved settings.
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The following table describes the labels in this screen.
15.3.1 Add/Edit a Service
Use this screen to add a customized service rule that you can use in the firewall’s ACL rule configuration.
Click Add new Protocol entry or the Edit icon next to an existing service rule in the Protocol screen to
display the following screen.
Figure 109 Security > Firewall > Protocol: Add/Edit
The following table describes the labels in this screen.
Table 79 Security > Firewall > Protocol
LABEL DESCRIPTION
Add New
Protocol Entry
Click this to add a new service.
Name This is the name of your customized service.
Description This is the description of your customized service.
Ports/Protocol
Number
This shows the IP protocol (TCP, UDP, ICMP, or TCP/UDP) and the port number or range of ports
that defines your customized service. Other and the protocol number displays if the service uses
another IP protocol.
Modify Click the Edit icon to edit the entry.
Click the Delete icon to remove this entry.
Table 80 Security > Firewall > Protocol: Add/Edit
LABEL DESCRIPTION
Service Name Enter a unique name (up to 32 printable English keyboard characters, including spaces) for your
customized port.
Description Enter a description for your customized port.
Protocol Choose the IP protocol (TCP, UDP, ICMP, or Other) that defines your customized port from the
drop-down list box. Select Other to be able to enter a protocol number.
Protocol
Number
This field is displayed if you select Other as the protocol.
Enter the protocol number of your customized port.
OK Click OK to save your changes.
Cancel Click Cancel to exit this screen without saving.
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15.4 The Access Control Screen
Click Securit y > Firewa ll > Acce ss Contro l to display the following screen. This screen displays a list of the
configured incoming or outgoing filtering rules.
Figure 110 Security > Firewall > Access Control
The following table describes the labels in this screen.
15.4.1 Add/Edit an ACL Rule
Click Add new ACL rule or the Edit icon next to an existing ACL rule in the Access Control screen. The
following screen displays.
Table 81 Security > Firewall > Access Control
LABEL DESCRIPTION
Add New ACL
Rule
Click this to go to add a filter rule for incoming or outgoing IP traffic.
#This is the index number of the entry.
Name This displays the name of the rule.
Src IP This displays the source IP addresses to which this rule applies. Please note that a blank source
address is equivalent to Any.
Dst IP This displays the destination IP addresses to which this rule applies. Please note that a blank
destination address is equivalent to Any.
Service This displays the transport layer protocol that defines the service and the direction of traffic to
which this rule applies.
Action This field displays whether the rule silently discards packets (DROP), discards packets and sends a
TCP reset packet or an ICMP destination-unreachable message to the sender (REJECT) or allows
the passage of packets (ACCEPT).
Modify Click the Edit icon to edit the rule.
Click the Delete icon to delete an existing rule. Note that subsequent rules move up by one
when you take this action.
Click the Move To icon to change the order of the rule. Enter the number in the # field.
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Figure 111 Access Control: Add/Edit
The following table describes the labels in this screen.
Table 82 Access Control: Add/Edit
LABEL DESCRIPTION
Filter Name Enter a descriptive name of up to 16 alphanumeric characters, not including spaces,
underscores, and dashes.
You must enter the filter name to add an ACL rule. This field is read-only if you are editing the
ACL rule.
Order Select the order of the ACL rule.
Select Source
Device
Select the source device to which the ACL rule applies. If you select Specific IP Address, enter
the source IP address in the field below.
Source IP
Address
Enter the source IP address.
Select
Destination
Device
Select the destination device to which the ACL rule applies. If you select Specific IP Address,
enter the destiniation IP address in the field below.
Destination IP
Address
Enter the destination IP address.
IP Type Select whether your IP type is IPv4 or IPv6.
Select Service Select the service rule that defines your customized port from the drop-down list box. The
specific service rule you add in the Security > Firewall > Protocol screen display in this list.
If you want to configure a customized service, select Specific Service.
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15.5 The DoS Screen
DoS (Denial of Service) attacks can flood your Internet connection with invalid packets and connection
requests, using so much bandwidth and so many resources that Internet access becomes unavailable.
Use the DoS screen to activate protection against DoS attacks. Click Security > Firewall > DoS to display
the following screen.
Figure 112 Security > Firewall > DoS
The following table describes the labels in this screen.
Protocol This field is displayed only when you select Specific Service in the Select Service field.
Choose the transport layer protocol (TCP/UDP, TCP, UDP, ICMP, or ICMPv6) that defines your
customized port from the drop-down list box.
Custom Source
Port
This field is displayed only when you select Specific Service in the Select Service field.
Enter a single port number or the range of port numbers of the source.
Custom
Destination Port
This field is displayed only when you select Specific Service in the Select Service field.
Enter a single port number or the range of port numbers of the destination.
Policy Use the drop-down list box to select whether to discard (DROP), deny and send an ICMP
destination-unreachable message to the sender of (REJECT) or allow the passage of (ACCEPT)
packets that match this rule.
Direction Use the drop-down list box to select the direction of traffic to which this rule applies.
Enable Rate
Limit
Select Enable to set a limit on the upstream/downstream transmission rate for the specified
protocol.
Specify how many packets per minute or second the transmission rate is.
Scheduler Rules Select a schedule rule for this ACL rule form the drop-down list box. You can configure a new
schedule rule by click Add New Rule. This will bring you to the Security > Scheduler Rules screen.
OK Click OK to save your changes.
Cancel Click Cancel to exit this screen without saving.
Table 82 Access Control: Add/Edit (continued)
LABEL DESCRIPTION
Table 83 Security > Firewall > DoS
LABEL DESCRIPTION
DoS Protection
Blocking
Select Enable to enable protection against DoS attacks.
Apply Click Apply to save your changes.
Cancel Click Cancel to exit this screen without saving.
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CHAPTER 16
MAC Filter
16.1 Overview
You can configure the VMG to permit access to clients based on their MAC addresses in the MAC Filter
screen. This applies to wired and wireless connections. Every Ethernet device has a unique MAC (Media
Access Control) address. The MAC address is assigned at the factory and consists of six pairs of
hexadecimal characters, for example, 00:A0:C5:00:00:02. You need to know the MAC addresses of the
devices to configure this screen.
16.2 The MAC Filter Screen
Use this screen to allow wireless and LAN clients access to the VMG. Click Security > MAC Filter. The
screen appears as shown.
Figure 113 Security > MAC Filter
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The following table describes the labels in this screen.
Table 84 Security > MAC Filter
LABEL DESCRIPTION
MAC Address Filter Select Enable to activate the MAC filter function.
MAC Restrict Mode Select Allow to only permit the listed MAC addresses access to the VMG. Select Deny to
permit anyone access to the VMG except the listed MAC addresses.
Set This is the index number of the MAC address.
Active Select Active to enable the MAC filter rule. The rule will not be applied if Active is not
selected.
Host Name Enter the host name of the wireless or LAN clients that are allowed access to the VMG.
MAC Address Enter the MAC addresses of the wireless or LAN clients that are allowed access to the VMG
in these address fields. Enter the MAC addresses in a valid MAC address format, that is, six
hexadecimal character pairs, for example, 12:34:56:78:9a:bc.
Apply Click Apply to save your changes.
Cancel Click Cancel to restore your previously saved settings.
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CHAPTER 17
Parental Control
17.1 Overview
Parental control allows you to block web sites with the specific URL. You can also define time periods
and days during which the VMG performs parental control on a specific user.
17.2 The Parental Control Screen
Use this screen to enable parental control, view the parental control rules and schedules.
Click Security > Parental Control to open the following screen.
Figure 114 Security > Parental Control
The following table describes the fields in this screen.
Table 85 Security > Parental Control
LABEL DESCRIPTION
Parental Control Select Enable to activate parental control.
Add New PCP Click this if you want to configure a new Parental Control Profile (PCP).
#This shows the index number of the rule.
Status This indicates whether the rule is active or not.
A yellow bulb signifies that this rule is active. A gray bulb signifies that this rule is not active.
PCP Name This shows the name of the rule.
Home Network
User MAC
This shows the MAC address of the LAN user’s computer to which this rule applies.
Internet Access
Schedule
This shows the day(s) and time on which parental control is enabled.
Network Service This shows whether the network service is configured. If not, None will be shown.
Website
Blocked
This shows whether the website block is configured. If not, None will be shown.
Modify Click the Edit icon to go to the screen where you can edit the rule.
Click the Delete icon to delete an existing rule.
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17.2.1 Add/Edit a Parental Control Profile
Click Add New PCP in the Parental Control screen to add a new rule or click the Edit icon next to an
existing rule to edit it. Use this screen to configure a restricted access schedule and/or URL filtering
settings to block the users on your network from accessing certain web sites.
Figure 115 Parental Control Rule: Add/Edit Rule
The following table describes the fields in this screen.
Apply Click Apply to save your changes.
Cancel Click Cancel to restore your previously saved settings.
Table 85 Security > Parental Control (continued)
LABEL DESCRIPTION
Table 86 Parental Control Rule: Add/Edit
LABEL DESCRIPTION
General
Active Select to enable or disable this parental control rule.
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Parental Control
Profile Name
Enter a descriptive name for the rule.
Home Network
User
Select the LAN user that you want to apply this rule to from the drop-down list box. If you select
Custom, enter the LAN user’s MAC address. If you select All, the rule applies to all LAN users.
Rule List In Home Network User, select Custom, enter the LAN user’s MAC address, then click the Add
icon to enter a computer MAC address for this PCP. Up to five are allowed. Click the Delete icon
to remove one.
Internet Access Schedule
Day Select check boxes for the days that you want the VMG to perform parental control.
Time (Start -
End)
Drag the time bar to define the time that the LAN user is allowed access (Authorized access) or
denied access (No access). Click the Add icon above the time bar to add a new time bar. Up
to three are allowed.
Network Service
Network Service
Setting
If you select Block, the VMG prohibits the users from viewing the Web sites with the URLs listed
below.
If you select Allow, the VMG blocks access to all URLs except ones listed below.
Add New
Service
Click this to show a screen in which you can add a new service rule. You can configure the
Service Name, Protocol, and Name of the new rule.
#This shows the index number of the rule.
Service Name This shows the name of the rule.
Protocol:Port This shows the protocol and the port of the rule.
Modify Click the Edit icon to go to the screen where you can edit the rule.
Click the Delete icon to delete an existing rule.
Site/URL Keyword
Block or Allow
the Web Site
If you select Block the Web URLs, the VMG prohibits the users from viewing the Web sites with the
URLs listed below.
If you select Allow the Web URLs, the VMG blocks access to all URLs except ones listed below.
Add Click Add to show a screen to enter the URL of web site or URL keyword to which the VMG blocks
or allows access.
#This shows the index number of the rule.
WebSite This shows the URL of web site or URL keyword to which the VMG blocks or allows access.
Modify Click the Edit icon to go to the screen where you can edit the rule.
Click the Delete icon to delete an existing rule.
Table 86 Parental Control Rule: Add/Edit (continued)
LABEL DESCRIPTION
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Click Security > Parental Control > Add New PCP > Add New Service to open the following screen.
Figure 117 Parental Control Rule: Add/Edit Rule > Add Service
The following table describes the fields in this screen.
Redirect
blocked site to
Zyxel Family
Safety page
Select this to redirect users who access any blocked websites listed above to the Zyxel Family
Safety page as shown next.
Figure 116 Zyxel Family Safety Page Example
OK Click OK to save your changes.
Cancel Click Cancel to to exit this screen without saving.
Table 87 Parental Control Rule: Add/Edit > Add New Service
LABEL DESCRIPTION
Service Name Select the name of the service. Otherwise, select User Define and manualy specify the protocol
and the port of the service.
If you have chosen a pre-defined service in the Service Name field, this field will not be
configurable.
Protocol Select the transport layer protocol used for the service. Choices are TCP, UDP, or TCP & UDP.
Port Enter the port of the service.
If you have chosen a pre-defined service in the Service Name field, this field will not be
configurable.
Table 86 Parental Control Rule: Add/Edit (continued)
LABEL DESCRIPTION
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Click Security > Parental Control > Add New PCP > Add to open the following screen.
Figure 118 Parental Control Rule: Add/Edit Rule > Add Keyword
The following table describes the fields in this screen.
OK Click OK to save your changes.
Cancel Click Cancel to exit this screen without saving.
Table 88 Parental Control Rule: Add/Edit > Add Keyword
LABEL DESCRIPTION
Site/URL
Keyword
Enter a keyword and click OK to have the VMG block access to the website URLs that contain
the keyword.
OK Click OK to save your changes.
Cancel Click Cancel to exit this screen without saving.
Table 87 Parental Control Rule: Add/Edit > Add New Service (continued)
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CHAPTER 18
Scheduler Rule
18.1 Overview
You can define time periods and days during which the VMG performs scheduled rules of certain
features (such as Firewall Access Control) in the Scheduler Rule screen.
18.2 The Scheduler Rule Screen
Use this screen to view, add, or edit time schedule rules.
Click Security > Scheduler Rule to open the following screen.
Figure 119 Security > Scheduler Rule
The following table describes the fields in this screen.
18.2.1 Add/Edit a Schedule
Click the Add New Rule button in the Scheduler Rule screen or click the Edit icon next to a schedule rule
to open the following screen. Use this screen to configure a restricted access schedule.
Table 89 Security > Scheduler Rule
LABEL DESCRIPTION
Add New Rule Click this to create a new rule.
#This is the index number of the entry.
Rule Name This shows the name of the rule.
Day This shows the day(s) on which this rule is enabled.
Time This shows the period of time on which this rule is enabled.
Description This shows the description of this rule.
Modify Click the Edit icon to edit the schedule.
Click the Delete icon to delete a scheduler rule.
Note: You cannot delete a scheduler rule once it is applied to a certain feature.
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Figure 120 Scheduler Rule: Add/Edit
The following table describes the fields in this screen.
Table 90 Scheduler Rule: Add/Edit
LABEL DESCRIPTION
Rule Name Enter a name (up to 31 printable English keyboard characters, not including spaces) for this
schedule.
Day Select check boxes for the days that you want the VMG to perform this scheduler rule.
Time of Day
Range
Enter the time period of each day, in 24-hour format, during which the rule will be enforced.
Description Enter a description for this scheduler rule.
OK Click OK to save your changes.
Cancel Click Cancel to exit this screen without saving.
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CHAPTER 19
Certificates
19.1 Overview
The VMG can use certificates (also called digital IDs) to authenticate users. Certificates are based on
public-private key pairs. A certificate contains the certificate owner’s identity and public key.
Certificates provide a way to exchange public keys for use in authentication.
19.1.1 What You Can Do in this Chapter
• The Local Certificates screen lets you generate certification requests and import the VMG's CA-signed
certificates (Section 19.4 on page 213).
• The Trusted CA screen lets you save the certificates of trusted CAs to the VMG (Section 19.4 on page
213).
19.2 What You Need to Know
The following terms and concepts may help as you read through this chapter.
Certification Authority
A Certification Authority (CA) issues certificates and guarantees the identity of each certificate owner.
There are commercial certification authorities like CyberTrust or VeriSign and government certification
authorities. The certification authority uses its private key to sign certificates. Anyone can then use the
certification authority's public key to verify the certificates. You can use the VMG to generate
certification requests that contain identifying information and public keys and then send the
certification requests to a certification authority.
19.3 The Local Certificates Screen
Click Security > Certificates to open the Local Certificates screen. This is the VMG’s summary list of
certificates and certification requests.
Figure 121 Security > Certificates > Local Certificates
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The following table describes the labels in this screen.
19.3.1 Create Certificate Request
Click Security > Certificates > Local Certificates and then Create Certificate Request to open the
following screen. Use this screen to have the VMG generate a certification request.
Table 91 Security > Certificates > Local Certificates
LABEL DESCRIPTION
Private Key is
protected by a
password
Select the checkbox and enter the private key into the text box to store it on the VMG. The
private key should not exceed 63 ASCII characters (not including spaces).
Choose File Click this to find the certificate file you want to upload.
Import Certificate Click this button to save the certificate that you have enrolled from a certification authority
from your computer to the VMG.
Create Certificate
Request
Click this button to go to the screen where you can have the VMG generate a certification
request.
Current File This field displays the name used to identify this certificate. It is recommended that you give
each certificate a unique name.
Subject This field displays identifying information about the certificate’s owner, such as CN (Common
Name), OU (Organizational Unit or department), O (Organization or company) and C
(Country). It is recommended that each certificate have unique subject information.
Issuer This field displays identifying information about the certificate’s issuing certification authority,
such as a common name, organizational unit or department, organization or company and
country.
Valid From This field displays the date that the certificate becomes applicable. The text displays in red
and includes a Not Yet Valid! message if the certificate has not yet become applicable.
Valid To This field displays the date that the certificate expires. The text displays in red and includes an
Expiring! or Expired! message if the certificate is about to expire or has already expired.
Modify Click the View icon to open a screen with an in-depth list of information about the certificate
(or certification request).
For a certification request, click Load Signed to import the signed certificate.
Click the Remove icon to delete the certificate (or certification request). You cannot delete a
certificate that one or more features is configured to use.
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Figure 122 Create Certificate Request
The following table describes the labels in this screen.
After you click Apply to generate a request, you still need to get the certificate request signed by a
Certificate Authority. If you already have, click the request’s Edit icon and then Load_Signed to import
the signed certificate into the VMG.
Table 92 Create Certificate Request
LABEL DESCRIPTION
Certificate
Name
Type up to 63 ASCII characters (not including spaces) to identify this certificate.
Common Name Select Auto to have the VMG configure this field automatically. Or select Customize to enter it
manually.
Type the IP address (in dotted decimal notation), domain name or e-mail address in the field
provided. The domain name or e-mail address can be up to 63 ASCII characters. The domain
name or e-mail address is for identification purposes only and can be any string.
Organization
Name
Type up to 63 characters to identify the company or group to which the certificate owner
belongs. You may use any character, including spaces, but the VMG drops trailing spaces.
State/Province
Name
Type up to 32 characters to identify the state or province where the certificate owner is located.
You may use any character, including spaces, but the VMG drops trailing spaces.
Country/Region
Name
Select a country to identify the nation where the certificate owner is located.
Apply Click Apply to save your changes.
Cancel Click Cancel to exit this screen without saving.
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Figure 123 Certificate Request Created
19.3.2 Load Signed Certificate
After you create a certificate request and have it signed by a Certificate Authority, in the View
Certificate screen click the certificate request’s Load_Signed button to import the signed certificate into
the VMG.
Note: You must remove any spaces from the certificate’s filename before you can import it.
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Figure 124 Load Signed Certificate
The following table describes the labels in this screen.
19.4 The Trusted CA Screen
Click Security > Certificates > Tru sted CA to open the following screen. This screen displays a summary list
of certificates of the certification authorities that you have set the VMG to accept as trusted. The VMG
accepts any valid certificate signed by a certification authority on this list as being trustworthy; thus you
do not need to import any certificate that is signed by one of these certification authorities.
Figure 125 Security > Certificates > Trusted CA
Table 93 Load Signed Certificate
LABEL DESCRIPTION
Certificate
Name
This is the name of the signed certificate.
Certificate Copy and paste the signed certificate into the text box to store it on the VMG.
Load_Signed Click Load_Signed to import the signed certificate into the VMG.
Cancel Click Cancel to exit this screen without saving.
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The following table describes the fields in this screen.
19.4.1 View Trusted CA Certificate
Click the View icon in the Trusted CA screen to open the following screen. Use this screen to view in-
depth information about the certification authority’s certificate.
Figure 126 Trusted CA: View
Table 94 Security > Certificates > Trusted CA
LABEL DESCRIPTION
Import
Certificate
Click this button to open a screen where you can save the certificate of a certification authority
that you trust to the VMG.
# This is the index number of the entry.
Name This field displays the name used to identify this certificate.
Subject This field displays information that identifies the owner of the certificate, such as Common Name
(CN), OU (Organizational Unit or department), Organization (O), State (ST) and Country (C). It is
recommended that each certificate have unique subject information.
Type This field displays general information about the certificate. ca means that a Certification
Authority signed the certificate.
Modify Click the View icon to open a screen with an in-depth list of information about the certificate (or
certification request).
Click the Remove button to delete the certificate (or certification request). You cannot delete a
certificate that one or more features is configured to use.
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The following table describes the fields in this screen.
19.4.2 Import Trusted CA Certificate
Click the Import Certificate button in the Trusted CA screen to open the following screen. The VMG trusts
any valid certificate signed by any of the imported trusted CA certificates.
Figure 127 Trusted CA: Import Certificate
The following table describes the fields in this screen.
Table 95 Trusted CA: View
LABEL DESCRIPTION
Name This field displays the identifying name of this certificate.
This read-only text box displays the certificate in Privacy Enhanced Mail (PEM) format. PEM uses
base 64 to convert the binary certificate into a printable form.
You can copy and paste the certificate into an e-mail to send to friends or colleagues or you
can copy and paste the certificate into a text editor and save the file on a management
computer for later distribution (via floppy disk for example).
Back Click Back to return to the previous screen.
Table 96 Trusted CA: Import Certificate
LABEL DESCRIPTION
Certificate File
Path
Type in the location of the certificate you want to upload in this field or click Choose File to find
it.
Apply Click Apply to save your changes.
Cancel Click Cancel to exit this screen without saving.
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CHAPTER 20
Log
20.1 Overview
The web configurator allows you to choose which categories of events and/or alerts to have the VMG
log and then display the logs or have the VMG send them to an administrator (as e-mail) or to a syslog
server.
20.1.1 What You Can Do in this Chapter
• Use the System Log screen to see the system logs (Section 20.2 on page 217).
• Use the Security Log screen to see the security-related logs for the categories that you select (Section
20.3 on page 217).
20.1.2 What You Need To Know
The following terms and concepts may help as you read this chapter.
Alerts and Logs
An alert is a type of log that warrants more serious attention. They include system errors, attacks (access
control) and attempted access to blocked web sites. Some categories such as System Errors consist of
both logs and alerts. You may differentiate them by their color in the View Log screen. Alerts display in
red and logs display in black.
Syslog Overview
The syslog protocol allows devices to send event notification messages across an IP network to syslog
servers that collect the event messages. A syslog-enabled device can generate a syslog message and
send it to a syslog server.
Syslog is defined in RFC 3164. The RFC defines the packet format, content and system log related
information of syslog messages. Each syslog message has a facility and severity level. The syslog facility
identifies a file in the syslog server. Refer to the documentation of your syslog program for details. The
following table describes the syslog severity levels.
Table 97 Syslog Severity Levels
CODE SEVERITY
0 Emergency: The system is unusable.
1 Alert: Action must be taken immediately.
2 Critical: The system condition is critical.
3 Error: There is an error condition on the system.
4 Warning: There is a warning condition on the system.
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20.2 The System Log Screen
Use the System Log screen to see the system logs. Click System Monitor > Log to open the System Log
screen.
Figure 128 System Monitor > Log > System Log
The following table describes the fields in this screen.
20.3 The Security Log Screen
Use the Security Log screen to see the security-related logs for the categories that you select. Click
System Monitor > Log > Security Log to open the following screen.
5 Notice: There is a normal but significant condition on the system.
6 Informational: The syslog contains an informational message.
7 Debug: The message is intended for debug-level purposes.
Table 97 Syslog Severity Levels
CODE SEVERITY
Table 98 System Monitor > Log > System Log
LABEL DESCRIPTION
Level Select a severity level from the drop-down list box. This filters search results according to the
severity level you have selected. When you select a severity, the VMG searches through all logs
of that severity or higher.
Category Select the type of logs to display.
Clear Log Click this to delete all the logs.
Refresh Click this to renew the log screen.
Export Log Click this to export the selected log(s).
Email Log Now Click this to send the log file(s) to the E-mail address you specify in the Maintenance > Logs
Setting screen.
#This field is a sequential value and is not associated with a specific entry.
Time This field displays the time the log was recorded.
Facility The log facility allows you to send logs to different files in the syslog server. Refer to the
documentation of your syslog program for more details.
Level This field displays the severity level of the log that the device is to send to this syslog server.
Category This field displays the type of the log.
Messages This field states the reason for the log.
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Figure 129 System Monitor > Log > Security Log
The following table describes the fields in this screen.
Table 99 System Monitor > Log > Security Log
LABEL DESCRIPTION
Level Select a severity level from the drop-down list box. This filters search results according to the
severity level you have selected. When you select a severity, the VMG searches through all logs
of that severity or higher.
Category Select the type of logs to display.
Clear Log Click this to delete all the logs.
Refresh Click this to renew the log screen.
Export Log Click this to export the selected log(s).
Email Log Now Click this to send the log file(s) to the E-mail address you specify in the Maintenance > Logs
Setting screen.
#This field is a sequential value and is not associated with a specific entry.
Time This field displays the time the log was recorded.
Facility The log facility allows you to send logs to different files in the syslog server. Refer to the
documentation of your syslog program for more details.
Level This field displays the severity level of the log that the device is to send to this syslog server.
Category This field displays the type of the log.
Messages This field states the reason for the log.
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CHAPTER 21
Traffic Status
21.1 Overview
Use the Traffic Status screens to look at network traffic status and statistics of the WAN, LAN interfaces
and NAT.
21.1.1 What You Can Do in this Chapter
• Use the WAN screen to view the WAN traffic statistics (Section 21.2 on page 219).
• Use the LAN screen to view the LAN traffic statistics (Section 21.3 on page 220).
• Use the NAT screen to view the NAT status of the VMG’s client(s) (Section 21.4 on page 221)
21.2 The WAN Status Screen
Click System Monitor > Traffic Status to open the WAN screen. The figure in this screen shows the number
of bytes received and sent on the VMG.
Figure 130 System Monitor > Traffic Status > WAN
The following table describes the fields in this screen.
Table 100 System Monitor > Traffic Status > WAN
LABEL DESCRIPTION
Refresh Interval Select how often you want the VMG to update this screen.
Connected
Interface
This shows the name of the WAN interface that is currently connected.
Packets Sent
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21.3 The LAN Status Screen
Click System Monitor > Traffic Status > LAN to open the following screen. The figure in this screen shows
the interface that is currently connected on the VMG.
Figure 131 System Monitor > Traffic Status > LAN
The following table describes the fields in this screen.
Data This indicates the number of transmitted packets on this interface.
Error This indicates the number of frames with errors transmitted on this interface.
Drop This indicates the number of outgoing packets dropped on this interface.
Packets Received
Data This indicates the number of received packets on this interface.
Error This indicates the number of frames with errors received on this interface.
Drop This indicates the number of received packets dropped on this interface.
Disabled
Interface
This shows the name of the WAN interface that is currently disconnected.
Packets Sent
Data This indicates the number of transmitted packets on this interface.
Error This indicates the number of frames with errors transmitted on this interface.
Drop This indicates the number of outgoing packets dropped on this interface.
Packets Received
Data This indicates the number of received packets on this interface.
Error This indicates the number of frames with errors received on this interface.
Drop This indicates the number of received packets dropped on this interface.
Table 100 System Monitor > Traffic Status > WAN (continued)
LABEL DESCRIPTION
Table 101 System Monitor > Traffic Status > LAN
LABEL DESCRIPTION
Refresh Interval Select how often you want the VMG to update this screen.
Interface This shows the LAN or WLAN interface.
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21.4 The NAT Status Screen
Click System Monitor > Traffic Status > NAT to open the following screen. The figure in this screen shows
the NAT session statistics for hosts currently connected on the VMG.
Figure 132 System Monitor > Traffic Status > NAT
The following table describes the fields in this screen.
Bytes Sent This indicates the number of bytes transmitted on this interface.
Bytes Received This indicates the number of bytes received on this interface.
Interface This shows the LAN or WLAN interfaces.
Sent (Packets)
Data This indicates the number of transmitted packets on this interface.
Error This indicates the number of frames with errors transmitted on this interface.
Drop This indicates the number of outgoing packets dropped on this interface.
Received (Packets)
Data This indicates the number of received packets on this interface.
Error This indicates the number of frames with errors received on this interface.
Drop This indicates the number of received packets dropped on this interface.
Table 101 System Monitor > Traffic Status > LAN (continued)
LABEL DESCRIPTION
Table 102 System Monitor > Traffic Status > NAT
LABEL DESCRIPTION
Refresh Interval Select how often you want the VMG to update this screen.
Device Name This displays the name of the connected host.
IP Address This displays the IP address of the connected host.
MAC Address This displays the MAC address of the connected host.
No. of Open
Sessions
This displays the number of NAT sessions currently opened for the connected host.
Total This displays what percentage of NAT sessions the VMG can support is currently being used by
all connected hosts. You can also see the number of active NAT sessions and the maximum
number of NAT sessions the VMG can support.
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CHAPTER 22
ARP Table
22.1 Overview
Address Resolution Protocol (ARP) is a protocol for mapping an Internet Protocol address (IP address) to
a physical machine address, also known as a Media Access Control or MAC address, on the local area
network.
An IP (version 4) address is 32 bits long. In an Ethernet LAN, MAC addresses are 48 bits long. The ARP
Table maintains an association between each MAC address and its corresponding IP address.
22.1.1 How ARP Works
When an incoming packet destined for a host device on a local area network arrives at the device, the
device's ARP program looks in the ARP Table and, if it finds the address, sends it to the device.
If no entry is found for the IP address, ARP broadcasts the request to all the devices on the LAN. The
device fills in its own MAC and IP address in the sender address fields, and puts the known IP address of
the target in the target IP address field. In addition, the device puts all ones in the target MAC field
(FF.FF.FF.FF.FF.FF is the Ethernet broadcast address). The replying device (which is either the IP address of
the device being sought or the router that knows the way) replaces the broadcast address with the
target's MAC address, swaps the sender and target pairs, and unicasts the answer directly back to the
requesting machine. ARP updates the ARP Table for future reference and then sends the packet to the
MAC address that replied.
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22.2 ARP Table Screen
Use the ARP table to view IP-to-MAC address mapping(s). To open this screen, click System Monitor >
ARP Table.
Figure 133 System Monitor > ARP Table
The following table describes the labels in this screen.
Table 103 System Monitor > ARP Table
LABEL DESCRIPTION
# This is the ARP table entry number.
IPv4/IPv6
Address
This is the learned IPv4 or IPv6 IP address of a device connected to a port.
MAC Address This is the MAC address of the device with the listed IP address.
Device This is the type of interface used by the device.
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CHAPTER 23
Routing Table
23.1 Overview
Routing is based on the destination address only and the VMG takes the shortest path to forward a
packet.
23.2 The Routing Table Screen
Click System Monitor > Routing Table to open the following screen.
Figure 134 System Monitor > Routing Table
The following table describes the labels in this screen.
Table 104 System Monitor > Routing Table
LABEL DESCRIPTION
IPv4/IPv6 Routing Table
Destination This indicates the destination IPv4 address or IPv6 address and prefix of this route.
Gateway This indicates the IPv4 address or IPv6 address of the gateway that helps forward this route’s
traffic.
Subnet Mask This indicates the destination subnet mask of the IPv4 route.
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Flag This indicates the route status.
U-Up: The route is up.
!-Reject: The route is blocked and will force a route lookup to fail.
G-Gateway: The route uses a gateway to forward traffic.
H-Host: The target of the route is a host.
R-Reinstate: The route is reinstated for dynamic routing.
D-Dynamic (redirect): The route is dynamically installed by a routing daemon or redirect.
M-Modified (redirect): The route is modified from a routing daemon or redirect.
Metric The metric represents the "cost of transmission". A router determines the best route for
transmission by choosing a path with the lowest "cost". The smaller the number, the lower the
"cost".
Interface This indicates the name of the interface through which the route is forwarded.
brx indicates a LAN interface where x can be 0~3 to represent LAN1 to LAN4 respectively.
nas8_x indicates a VDSL WAN interface using IPoE or in bridge mode.
nasx indicates an ADSL WAN interface using IPoE, IPoA or in bridge mode.
nas10_x indicates an Ethernet WAN interface using IPoE or in bridge mode.
ppp0 indicates a WAN interface using PPPoE or PPPoA.
Table 104 System Monitor > Routing Table (continued)
LABEL DESCRIPTION
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CHAPTER 24
xDSL Statistics
24.1 The xDSL Statistics Screen
Use this screen to view detailed DSL statistics. Click System Monitor > xDSL Statistics to open the following
screen.
Figure 135 System Monitor > xDSL Statistics
The following table describes the labels in this screen.
Table 105 Status > xDSL Statistics
LABEL DESCRIPTION
Refresh Interval Select the time interval for refreshing statistics.
Line Select which DSL line’s statistics you want to display.
xDSLFwVersion This displays the current firmware and hardware versions of the VMG.
Line State This displays the current state of the DSL connection.
Modulation This displays the modulation method of the DSL connection.
Annex Mode This displays the annex mode of the DSL connection.
Downstream These are the statistics for the traffic direction coming into the port from the service provider.
Upstream These are the statistics for the traffic direction going out from the port to the service provider.
SNR Margin This is the upstream and downstream Signal-to-Noise Ratio margin (in dB). A DMT sub-carrier’s
SNR is the ratio between the received signal power and the received noise power. The signal-
to-noise ratio margin is the maximum that the received noise power could increase with the
system still being able to meet its transmission targets.
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Line Attenuation This is the upstream and downstream line attenuation, measured in decibels (dB). This
attenuation is the difference between the power transmitted at the near-end and the power
received at the far-end. Attenuation is affected by the channel characteristics (wire gauge,
quality, condition and length of the physical line).
Data Rate These are the data transfer rates at which the port is sending and receiving data.
ES This is the number of Errored Seconds meaning the number of seconds containing at least one
errored block or at least one defect.
SES This is the number of Severely Errored Seconds meaning the number of seconds containing 30%
or more errored blocks or at least one defect. This is a subset of ES.
Table 105 Status > xDSL Statistics (continued)
LABEL DESCRIPTION
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CHAPTER 25
Cellular Statistics
25.1 Overview
Use the Cellular Statistics screens to look at cellular Internet connection status.
25.2 The Cellular Statistics Screen
To open this screen, click System Monitor > Cellular Statistics. The Cellular status is available on this
screen only when you insert a compatible cellular dongle in a USB port on the VMG.
Figure 136 System Monitor > Cellular Statistics
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The following table describes the labels in this screen.
Table 106 System Monitor > Cellular Statistics
LABEL DESCRIPTION
Refresh Interval Select how often you want the VMG to update this screen. Select No Refresh to stop refreshing.
Cellular Status This field displays the status of the cellular Internet connection. This field can display:
GSM - Global System for Mobile Communications, 2G
GPRS - General Packet Radio Service, 2.5G
EDGE - Enhanced Data rates for GSM Evolution, 2.75G
WCDMA - Wideband Code Division Multiple Access, 3G
HSDPA - High-Speed Downlink Packet Access, 3.5G
HSUPA - High-Speed Uplink Packet Access, 3.75G
HSPA - HSDPA+HSUPA, 3.75G
Service Provider This field displays the name of the service provider.
Signal Strength This field displays the strength of the signal in dBm.
Connection
Uptime
This field displays the time the connection has been up.
Cellular Card
Manufacturer
This field displays the manufacturer of the cellular card.
Cellular Card
Model
This field displays the model name of the cellular card.
Cellular Card F/
W Version
This field displays the firmware version of the cellular card.
SIM Card IMSI The International Mobile Subscriber Identity or IMSI is a unique identification number associated
with all cellular networks. This number is provisioned in the SIM card.
VID/PID This field displays the USB Vendor ID and Product ID of the cellular card.
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CHAPTER 26
System
26.1 Overview
In the System screen, you can name your VMG (Host) and give it an associated domain name for
identification purposes.
26.2 The System Screen
Click Maintenance > System to open the following screen.
Figure 137 Maintenance > System
The following table describes the labels in this screen.
Table 107 Maintenance > System
LABEL DESCRIPTION
Host Name Type a hostname for your VMG. Enter a descriptive name of up to 16 alphanumeric characters,
not including spaces, underscores, and dashes.
Domain Name Type a Domain name for your host VMG.
Apply Click Apply to save your changes.
Cancel Click Cancel to abandon this screen without saving.
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CHAPTER 27
User Account
27.1 Overview
In the User Account screen, you can view the settings of the “admin” and other user accounts that you
used to log in the VMG.
27.2 The User Account Screen
Click Maintenance > User Account to open the following screen.
Figure 138 Maintenance > User Account
The following table describes the labels in this screen.
Table 108 Maintenance > User Account
LABEL DESCRIPTION
Add New
Account
Click this button to add a new user account.
#This is the index number
Active This field indicates whether the user account is active or not.
Clear the check box to disable the user account. Select the check box to enable it.
User Name This field displays the name of the account used to log into the VMG web configurator.
Retry Times This field displays the number of times consecutive wrong passwords can be entered for this
account. 0 means there is no limit.
Idle Timeout This field displays the the length of inactive time before the VMG will automatically log the user
out of the web configurator.
Lock Period This field displays the length of time a user must wait before attempting to log in again after a
number if consecutive wrong passwords have been entered as defined in Retry Times.
Group This field displays whether this user has Administrator or User privleges.
Modify Click the Edit icon to configure the entry.
Click the Delete icon to remove the entry.
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27.2.1 The User Account Add and Edit Screens
Click Add New Account or the Edit icon of an existing account in the Maintenance > User Account to
open the following screen.
Figure 139 Maintenance > User Account > Add/Edit
The following table describes the labels in this screen.
Table 109 Maintenance > User Account > Add/Edit
LABEL DESCRIPTION
Active This field indicates whether the user account is active or not.
Clear the check box to disable the user account. Select the check box to enable it.
User Name Enter a new name for the account. This field displays the name of an existing account.
Old Password Type the default password or the existing password used to access the VMG web configurator.
Password/New
Password
Type a new password (up to 256 characters) for this account. Note that as you type a password,
the screen displays a (*) for each character you type. After you change the password, use the
new password to access the VMG.
Verify Password/
Verify New
Password
Type the new password again for confirmation.
Retry Times Enter the number of times consecutive wrong passwords can be entered for this account. 0
means there is no limit.
Idle Timeout Enter the length of inactive time before the VMG will automatically log the user out of the web
configurator.
Lock Period Enter the length of time a user must wait before attempting to log in again after a number if
consecutive wrong passwords have been entered as defined in Retry Times.
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Group Specify whether this user will have Administrator or User privleges.
OK Click OK to save your changes.
Cancel Click Cancel to exit this screen without saving.
Table 109 Maintenance > User Account > Add/Edit (continued) (continued)
LABEL DESCRIPTION
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CHAPTER 28
Remote Management
28.1 Overview
Remote management controls through which interface(s), which services can access the VMG.
Note: The VMG is managed using the Web Configurator.
28.2 The Remote MGMT Screen
Use this screen to configure through which interface(s), which services can access the VMG. You can
also specify the port numbers the services must use to connect to the VMG. Click Maintenance >
Remote MGMT to open the following screen.
Figure 140 Maintenance > Remote MGMT
The following table describes the fields in this screen.
Table 110 Maintenance > Remote MGMT
LABEL DESCRIPTION
WAN Interface
used for services
Select Any_WAN to have the VMG automatically activate the remote management service
when any WAN connection is up.
Select Multi_WAN and then select one or more WAN connections to have the VMG activate the
remote management service when the selected WAN connections are up.
service This is the service you may use to access the VMG.
LAN/WLAN Select the Enable check box for the corresponding services that you want to allow access to the
VMG from the LAN/WLAN.
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28.3 The Trust Domain Screen
Use this screen to view a list of public IP addresses which are allowed to access the VMG through the
services configured in the Maintenance > Remote MGMT screen. Click Maintenance > Remote MGMT >
Turst Domain to open the following screen.
Note: If this list is empty, all public IP addresses can access the VMG from the WAN through
the specified services.
Figure 141 Maintenance > Remote MGMT > Trust Domain
The following table describes the fields in this screen.
28.3.1 The Add Trust Domain Screen
Use this screen to configure a public IP address which is allowed to access the VMG. Click the Add Trust
Domain button in the Maintenance > Rem ote MGMT > Turst Domain screen to open the following screen.
WAN Select the Enable check box for the corresponding services that you want to allow access to the
VMG from all WAN connections.
Trust Domain Select the Enable check box for the corresponding services that you want to allow access to the
VMG from the trusted hosts configured in the Maintenance > Remote MGMT > Trust Domain
screen.
If you only want certain WAN connections to have access to the VMG using the corresponding
services, then clear WAN, select Trust Domain and configure the allowed IP address(es) in the
Trust Domain screen.
Port You may change the server port number for a service if needed, however you must use the
same port number in order to use that service for remote management.
Apply Click Apply to save your changes back to the VMG.
Cancel Click Cancel to restore your previously saved settings.
Table 110 Maintenance > Remote MGMT (continued)
LABEL DESCRIPTION
Table 111 Maintenance > Remote MGMT > Trust Domain
LABEL DESCRIPTION
Add Trust
Domain
Click this to add a trusted host IP address.
IP Address This field shows a trusted host IP address.
Delete Click the Delete icon to remove the trust IP address.
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Figure 142 Maintenance > Remote MGMT > Trust Domain > Add Trust Domain
The following table describes the fields in this screen.
Table 112 Maintenance > Remote MGMT > Trust Domain > Add Trust Domain
LABEL DESCRIPTION
IP Address Enter a public IPv4 IP address which is allowed to access the service on the VMG from the WAN.
OK Click OK to save your changes back to the VMG.
Cancel Click Cancel to exit this screen without saving.
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CHAPTER 29
SNMP
29.1 Overview
This chapter explains how to configure the SNMP settings on the VMG.
29.2 The SNMP Screen
Simple Network Management Protocol is a protocol used for exchanging management information
between network devices. Your VMG supports SNMP agent functionality, which allows a manager
station to manage and monitor the VMG through the network. The VMG supports SNMP version one
(SNMPv1) and version two (SNMPv2c). The next figure illustrates an SNMP management operation.
Figure 143 SNMP Management Model
An SNMP managed network consists of two main types of component: agents and a manager.
An agent is a management software module that resides in a managed device (the VMG). An agent
translates the local management information from the managed device into a form compatible with
SNMP. The manager is the console through which network administrators perform network management
functions. It executes applications that control and monitor managed devices.
The managed devices contain object variables/managed objects that define each piece of
information to be collected about a device. Examples of variables include such as number of packets
received, node port status etc. A Management Information Base (MIB) is a collection of managed
objects. SNMP allows a manager and agents to communicate for the purpose of accessing these
objects.
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SNMP itself is a simple request/response protocol based on the manager/agent model. The manager
issues a request and the agent returns responses using the following protocol operations:
• Get - Allows the manager to retrieve an object variable from the agent.
• GetNext - Allows the manager to retrieve the next object variable from a table or list within an agent.
In SNMPv1, when a manager wants to retrieve all elements of a table from an agent, it initiates a Get
operation, followed by a series of GetNext operations.
• Set - Allows the manager to set values for object variables within an agent.
• Trap - Used by the agent to inform the manager of some events.
Click Maintenance > SNMP to open the following screen. Use this screen to configure the VMG SNMP
settings.
Figure 144 Maintenance > SNMP
The following table describes the fields in this screen.
Table 113 Maintenance > SNMP
LABEL DESCRIPTION
SNMP Agent Select Enable to let the VMG act as an SNMP agent, which allows a manager station to
manage and monitor the VMG through the network. Select Disable to turn this feature off.
Get Community Enter the Get Community, which is the password for the incoming Get and GetNext requests
from the management station.
Set Community Enter the Set community, which is the password for incoming Set requests from the
management station.
Trap Community Enter the Trap Community, which is the password sent with each trap to the SNMP manager.
The default is public and allows all requests.
System Name Enter the SNMP system name.
System Location Enter the SNMP system location.
System Contact Enter the SNMP system contact.
Trap Destination Type the IP address of the station to send your SNMP traps to.
Apply Click this to save your changes back to the VMG.
Cancel Click this to restore your previously saved settings.
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CHAPTER 30
Time Settings
30.1 Overview
This chapter shows you how to configure system related settings, such as system time, password, name,
the domain name and the inactivity timeout interval.
30.2 The Time Screen
To change your VMG’s time and date, click Maintenance > Time. The screen appears as shown. Use this
screen to configure the VMG’s time based on your local time zone.
Figure 145 Maintenance > Time
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The following table describes the fields in this screen.
Table 114 Maintenance > Time
LABEL DESCRIPTION
Current Date/Time
Current Time This field displays the time of your VMG.
Each time you reload this page, the VMG synchronizes the time with the time server.
Current Date This field displays the date of your VMG.
Each time you reload this page, the VMG synchronizes the date with the time server.
Time and Date Setup
First ~ Fifth Time
Server Address
Select an NTP time server from the drop-down list box.
Otherwise, select Other and enter the IP address or URL (up to 29 extended ASCII characters
in length) of your time server.
Select None if you don’t want to configure the time server.
Check with your ISP/network administrator if you are unsure of this information.
Time Zone
Time zone Choose the time zone of your location. This will set the time difference between your time
zone and Greenwich Mean Time (GMT).
Daylight Savings Daylight Saving Time is a period from late spring to early fall when many countries set their
clocks ahead of normal local time by one hour to give more daytime light in the evening.
Active Select Enable if you use Daylight Saving Time.
Start Rule Configure the day and time when Daylight Saving Time starts if you enabled Daylight Saving.
You can select a specific date in a particular month or a specific day of a specific week in a
particular month. The Hour field uses the 24 hour format. Here are a couple of examples:
Daylight Saving Time starts in most parts of the United States on the second Sunday of March.
Each time zone in the United States starts using Daylight Saving Time at 2 A.M. local time. So in
the United States, set the day to Second, Sunday, the month to March and the time to 2 in the
Hour field.
Daylight Saving Time starts in the European Union on the last Sunday of March. All of the time
zones in the European Union start using Daylight Saving Time at the same moment (1 A.M.
GMT or UTC). So in the European Union you would set the day to Last, Sunday and the month
to March. The time you select depends on your time zone. In Germany for instance, you
would select 2 in the Hour field because Germany's time zone is one hour ahead of GMT or
UTC (GMT+1).
End Rule Configure the day and time when Daylight Saving Time ends if you enabled Daylight Saving.
You can select a specific date in a particular month or a specific day of a specific week in a
particular month. The Time field uses the 24 hour format. Here are a couple of examples:
Daylight Saving Time ends in the United States on the first Sunday of November. Each time
zone in the United States stops using Daylight Saving Time at 2 A.M. local time. So in the United
States you would set the day to First, Sunday, the month to November and the time to 2 in the
Time field.
Daylight Saving Time ends in the European Union on the last Sunday of October. All of the
time zones in the European Union stop using Daylight Saving Time at the same moment (1
A.M. GMT or UTC). So in the European Union you would set the day to Last, Sunday, and the
month to October. The time you select depends on your time zone. In Germany for instance,
you would select 2 in the Time field because Germany's time zone is one hour ahead of GMT
or UTC (GMT+1).
Apply Click Apply to save your changes.
Cancel Click Cancel to return to the previous configuration.
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CHAPTER 31
E-mail Notification
31.1 Overview
A mail server is an application or a computer that runs such an application to receive, forward and
deliver e-mail messages.
To have the VMG send reports, logs or notifications via e-mail, you must specify an e-mail server and the
e-mail addresses of the sender and receiver.
31.2 The E-mail Notification Screen
Click Maintenance > E-mail Notification to open the E-mail Notification screen. Use this screen to view,
remove and add mail server information on the VMG.
Figure 146 Maintenance > E-mail Notification
The following table describes the labels in this screen.
31.2.1 E-mail Notification Edit
Click the Add New E-mail button in the E-mail Notification screen. Use this screen to configure the
required information for sending e-mail via a mail server.
Table 115 Maintenance > E-mail Notification
LABEL DESCRIPTION
Add New Email Click this button to create a new entry.
Mail Server
Address
This field displays the server name or the IP address of the mail server.
Username This field displays the user name of the sender’s mail account.
Port This field displays the port number of the mail server.
Security This field displays the protocol used for encryption.
Email Address This field displays the e-mail address that you want to be in the from/sender line of the e-mail
that the VMG sends.
Remove Click this button to delete the selected entry(ies).
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Figure 147 E-mail Notification > Add New E-mail
The following table describes the labels in this screen.
Table 116 E-mail Notification > Add
LABEL DESCRIPTION
Mail Server
Address
Enter the server name or the IP address of the mail server for the e-mail address specified in the
Account E-mail Address field.
If this field is left blank, reports, logs or notifications will not be sent via e-mail.
Port Enter the same port number here as is on the mail server for mail traffic.
Authentication
Username
Enter the user name (up to 32 characters). This is usually the user name of a mail account you
specified in the Account E-mail Address field.
Authentication
Password
Enter the password associated with the user name above.
Account E-mail
Address
Enter the e-mail address that you want to be in the from/sender line of the e-mail notification
that the VMG sends.
If you activate SSL/TLS authentication, the e-mail address must be able to be authenticated by
the mail server as well.
Connection
Security
Select SSL to use Secure Sockets Layer (SSL) or Transport Layer Security (TLS) if you want
encrypted communications between the mail server and the VMG.
Select STARTTLS to upgrade a plain text connection to a secure connection using SSL/TLS.
OK Click this button to save your changes and return to the previous screen.
Cancel Click this button to exit this screen without saving.
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CHAPTER 32
Logs Setting
32.1 Overview
You can configure where the VMG sends logs and which logs and/or immediate alerts the VMG records
in the Logs Setting screen.
32.2 The Logs Setting Screen
To change your VMG’s log settings, click Maintenance > Logs Setting. The screen appears as shown.
Figure 148 Maintenance > Logs Setting
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The following table describes the fields in this screen.
32.2.1 Example E-mail Log
An "End of Log" message displays for each mail in which a complete log has been sent. The following is
an example of a log sent by e-mail.
• You may edit the subject title.
• The date format here is Day-Month-Year.
• The date format here is Month-Day-Year. The time format is Hour-Minute-Second.
•"End of Log" message shows that a complete log has been sent.
Table 117 Maintenance > Logs Setting
LABEL DESCRIPTION
Syslog Setting
Syslog Logging The VMG sends a log to an external syslog server. Select Enable to enable syslog logging.
Mode Select the syslog destination from the drop-down list box.
If you select Remote, the log(s) will be sent to a remote syslog server. If you select Local File, the
log(s) will be saved in a local file. If you want to send the log(s) to a remote syslog server and
save it in a local file, select Local File and Remote.
Syslog Server Enter the server name or IP address of the syslog server that will log the selected categories of
logs.
UDP Port Enter the port number used by the syslog server.
E-mail Log Settings
E-mail Log
Settings
Select Enable to have the VMG send logs and alarm messages to the configured e-mail
addresses.
Mail
Account This section is available only when you select Enable in the E-mail Log Settings field.
Select a mail account from which you want to send logs. You can configure mail accounts in
the Maintenance > E-mail Notification screen.
System Log
Mail Subject Type a title that you want to be in the subject line of the system log e-mail message that the
VMG sends.
Security Log
Mail Subject Type a title that you want to be in the subject line of the security log e-mail message that the
VMG sends.
Send Log to The VMG sends logs to the e-mail address specified in this field. If this field is left blank, the VMG
does not send logs via E-mail.
Send Alarm
to Alerts are real-time notifications that are sent as soon as an event, such as a DoS attack, system
error, or forbidden web access attempt occurs. Enter the E-mail address where the alert
messages will be sent. Alerts include system errors, attacks and attempted access to blocked
web sites. If this field is left blank, alert messages will not be sent via E-mail.
Alarm
Interval Specify how often the alarm should be updated.
Active Log
System Log Select the categories of system logs that you want to record.
Security Log Select the categories of security logs that you want to record.
Apply Click Apply to save your changes.
Cancel Click Cancel to restore your previously saved settings.
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Figure 149 E-mail Log Example
Subject:
Firewall Alert From
Date:
Fri, 07 Apr 2000 10:05:42
From:
user@zyxel.com
To:
user@zyxel.com
1|Apr 7 00 |From:192.168.1.1 To:192.168.1.255 |default policy |forward
| 09:54:03 |UDP src port:00520 dest port:00520 |<1,00> |
2|Apr 7 00 |From:192.168.1.131 To:192.168.1.255 |default policy |forward
| 09:54:17 |UDP src port:00520 dest port:00520 |<1,00> |
3|Apr 7 00 |From:192.168.1.6 To:10.10.10.10 |match |forward
| 09:54:19 |UDP src port:03516 dest port:00053 |<1,01> |
……………………………..{snip}…………………………………..
……………………………..{snip}…………………………………..
126|Apr 7 00 |From:192.168.1.1 To:192.168.1.255 |match |forward
| 10:05:00 |UDP src port:00520 dest port:00520 |<1,02> |
127|Apr 7 00 |From:192.168.1.131 To:192.168.1.255 |match |forward
| 10:05:17 |UDP src port:00520 dest port:00520 |<1,02> |
128|Apr 7 00 |From:192.168.1.1 To:192.168.1.255 |match |forward
| 10:05:30 |UDP src port:00520 dest port:00520 |<1,02> |
End of Firewall Log
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CHAPTER 33
Firmware Upgrade
33.1 Overview
This chapter explains how to upload new firmware to your VMG. You can download new firmware
releases from your nearest Zyxel FTP site (or www.zyxel.com) to use to upgrade your device’s
performance.
Only use firmware for your device’s specific model. Refer to the label on
the bottom of your VMG.
33.2 The Firmware Screen
Click Maintenance > Firmware Upgrade to open the following screen. The upload process uses HTTP
(Hypertext Transfer Protocol) and may take up to two minutes. After a successful upload, the system will
reboot.
Do NOT turn off the VMG while firmware upload is in progress!
Figure 150 Maintenance > Firmware Upgrade
The following table describes the labels in this screen. After you see the firmware updating screen, wait
two minutes before logging into the VMG again.
Table 118 Maintenance > Firmware Upgrade
LABEL DESCRIPTION
Upgrade
Firmware
Restore
Default
Settings After
Firmware
Upgrade
Click the check box to have the VMG automatically reset itself after the new firmware is
uploaded.
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Figure 151 Firmware Uploading
The VMG automatically restarts in this time causing a temporary network disconnect. In some operating
systems, you may see the following icon on your desktop.
Figure 152 Network Temporarily Disconnected
After two minutes, log in again and check your new firmware version in the Status screen.
If the upload was not successful, the following screen will appear. Click OK to go back to the Firmware
Upgrade screen.
Figure 153 Error Message
Current
Firmware
Version
This is the present Firmware version and the date created.
File Path Type in the location of the file you wasnt to upload in this field or click Choose File to find it.
Choose File Click this to find the .bin file you want to upload. Remember that you must decompress
compressed (.zip) files before you can upload them.
Upload Click this to begin the upload process. This process may take up to two minutes.
Upgrade WWAN
Package
Current
WWAN
Package
Version
This is the present WWAN Package version and the date created.
File Path Type in the location of the file you want to upload in this field or click Choose File to find it.
Choose File Click this to find the .bin file you want to upload. Remember that you must decompress
compressed (.zip) files before you can upload them.
Upload Click this to begin the upload process. This process may take up to two minutes.
Table 118 Maintenance > Firmware Upgrade
LABEL DESCRIPTION
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CHAPTER 34
Backup/Restore
34.1 Overview
The Backup/Restore screen allows you to backup and restore device configurations. You can also reset
your device settings back to the factory default.
34.2 The Backup/Restore Screen
Click Maintenance > Backup/Restore. Information related to factory defaults, backup configuration,
and restoring configuration appears in this screen, as shown next.
Figure 154 Maintenance > Backup/Restore
Backup Configuration
Backup Configuration allows you to back up (save) the VMG’s current configuration to a file on your
computer. Once your VMG is configured and functioning properly, it is highly recommended that you
back up your configuration file before making configuration changes. The backup configuration file will
be useful in case you need to return to your previous settings.
Click Backup to save the VMG’s current configuration to your computer.
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Restore Configuration
Restore Configuration allows you to upload a new or previously saved configuration file from your
computer to your VMG.
Do not turn off the VMG while configuration file upload is in progress.
After the VMG configuration has been restored successfully, the login screen appears. Login again to
restart the VMG.
The VMG automatically restarts in this time causing a temporary network disconnect. In some operating
systems, you may see the following icon on your desktop.
Figure 155 Network Temporarily Disconnected
If you uploaded the default configuration file you may need to change the IP address of your computer
to be in the same subnet as that of the default device IP address (192.168.1.1).
If the upload was not successful, the following screen will appear. Click OK to go back to the
Configuration screen.
Figure 156 Configuration Upload Error
Reset to Factory Defaults
Click the Reset button to clear all user-entered configuration information and return the VMG to its
factory defaults. The following warning screen appears.
Table 119 Restore Configuration
LABEL DESCRIPTION
File Path Type in the location of the file you want to upload in this field or click Choose File to find it.
Choose File Click this to find the file you want to upload. Remember that you must decompress compressed
(.ZIP) files before you can upload them.
Upload Click this to begin the upload process.
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Figure 157 Reset Warning Message
Figure 158 Reset In Process Message
You can also press the RESET button on the rear panel to reset the factory defaults of your VMG. Refer to
Section 1.6.6 on page 24 for more information on the RESET button.
34.3 The Reboot Screen
System restart allows you to reboot the VMG remotely without turning the power off. You may need to
do this if the VMG hangs, for example.
Click Maintenance > Reboot. Click Reboot to have the VMG reboot. This does not affect the VMG's
configuration.
Figure 159 Maintenance > Reboot
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CHAPTER 35
Diagnostic
35.1 Overview
The Diagnostic screens display information to help you identify problems with the VMG.
The route between a CO VDSL switch and one of its CPE may go through switches owned by
independent organizations. A connectivity fault point generally takes time to discover and impacts
subscriber’s network access. In order to eliminate the management and maintenance efforts, IEEE
802.1ag is a Connectivity Fault Management (CFM) specification which allows network administrators to
identify and manage connection faults. Through discovery and verification of the path, CFM can
detect, analyze and isolate connectivity faults in bridged LANs.
35.1.1 What You Can Do in this Chapter
• The Ping & TraceRoute & Nslookup screen lets you ping an IP address or trace the route packets take
to a host (Section 35.3 on page 252).
35.2 What You Need to Know
The following terms and concepts may help as you read through this chapter.
How CFM Works
A Maintenance Association (MA) defines a VLAN and associated Maintenance End Point (MEP) ports
on the device under a Maintenance Domain (MD) level. An MEP port has the ability to send
Connectivity Check Messages (CCMs) and get other MEP ports information from neighbor devices’
CCMs within an MA.
CFM provides two tests to discover connectivity faults.
• Loopback test - checks if the MEP port receives its Loop Back Response (LBR) from its target after it
sends the Loop Back Message (LBM). If no response is received, there might be a connectivity fault
between them.
• Link trace test - provides additional connectivity fault analysis to get more information on where the
fault is. If an MEP port does not respond to the source MEP, this may indicate a fault. Administrators
can take further action to check and resume services from the fault according to the line
connectivity status report.
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35.3 Ping & TraceRoute & Nslookup
Use this screen to ping, traceroute, or nslookup an IP address. Click Maintenance > Diagnostic >
Ping&TraceRoute&Nslookup to open the screen shown next.
Figure 160 Maintenance > Diagnostic > Ping&TraceRoute&Nslookup
The following table describes the fields in this screen.
Table 120 Maintenance > Diagnostic > Ping & TraceRoute & Nslookup
LABEL DESCRIPTION
TCP/IP Address Type the IP address of a computer that you want to perform ping, traceroute, or nslookup in
order to test a connection.
Ping Click this to ping the IPv4 address that you entered.
Ping 6 Click this to ping the IPv6 address that you entered.
TraceRoute Click this to display the route path and transmission delays between the VMG to the IPv4
address that you entered.
TraceRoute 6 Click this to display the route path and transmission delays between the VMG to the IPv6
address that you entered.
Nslookup Click this button to perform a DNS lookup on the IP address of a computer you enter.
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CHAPTER 36
Troubleshooting
This chapter offers some suggestions to solve problems you might encounter. The potential problems are
divided into the following categories.
•Power, Hardware Connections, and LEDs
•VMG Access and Login
•Internet Access
•Wireless Internet Access
•USB Device Connection
•UPnP
36.1 Power, Hardware Connections, and LEDs
The VMG does not turn on. None of the LEDs turn on.
1Make sure the VMG is turned on.
2Make sure you are using the power adaptor or cord included with the VMG.
3Make sure the power adaptor or cord is connected to the VMG and plugged in to an appropriate
power source. Make sure the power source is turned on.
4Turn the VMG off and on.
5If the problem continues, contact the vendor.
One of the LEDs does not behave as expected.
1Make sure you understand the normal behavior of the LED. See Section 1.6.2 on page 20.
2Check the hardware connections.
3Inspect your cables for damage. Contact the vendor to replace any damaged cables.
4Turn the VMG off and on.
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5If the problem continues, contact the vendor.
36.2 VMG Access and Login
I forgot the IP address for the VMG.
1The default LAN IP address is 192.168.1.1.
2If you changed the IP address and have forgotten it, you might get the IP address of the VMG by
looking up the IP address of the default gateway for your computer. To do this in most Windows
computers, click Start > R un, enter cmd, and then enter ipconfig. The IP address of the Default Gateway
might be the IP address of the VMG (it depends on the network), so enter this IP address in your Internet
browser.
3If this does not work, you have to reset the device to its factory defaults. See Section 1.6.6 on page 24.
I forgot the password.
1See the cover page for the default login names and associated passwords.
2If those do not work, you have to reset the device to its factory defaults. See Section 1.6.6 on page 24.
I cannot see or access the Login screen in the web configurator.
1Make sure you are using the correct IP address.
• The default IP address is 192.168.1.1.
• If you changed the IP address (Section 8.2 on page 125), use the new IP address.
• If you changed the IP address and have forgotten it, see the troubleshooting suggestions for I
forgot the IP address for the VMG.
2Check the hardware connections, and make sure the LEDs are behaving as expected. See Section 1.6.2
on page 20.
3Make sure your Internet browser does not block pop-up windows and has JavaScripts and Java
enabled.
4If it is possible to log in from another interface, check the service control settings for HTTP and HTTPS
(Maintenance > Remote MGMT).
5Reset the device to its factory defaults, and try to access the VMG with the default IP address. See
Section 1.6.6 on page 24.
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6If the problem continues, contact the network administrator or vendor, or try one of the advanced
suggestions.
Advanced Suggestions
• Make sure you have logged out of any earlier management sessions using the same user account
even if they were through a different interface or using a different browser.
• Try to access the VMG using another service, such as Telnet. If you can access the VMG, check the
remote management settings and firewall rules to find out why the VMG does not respond to HTTP.
I can see the Login screen, but I cannot log in to the VMG.
1Make sure you have entered the password correctly. See the cover page for the default login names
and associated passwords. The field is case-sensitive, so make sure [Caps Lock] is not on.
2You cannot log in to the web configurator while someone is using Telnet to access the VMG. Log out of
the VMG in the other session, or ask the person who is logged in to log out.
3Turn the VMG off and on.
4If this does not work, you have to reset the device to its factory defaults. See Section 36.1 on page 253.
I cannot Telnet to the VMG.
See the troubleshooting suggestions for I cannot see or access the Login screen in the web configurator.
Ignore the suggestions about your browser.
I cannot use FTP to upload / download the configuration file. / I cannot use FTP to upload new
firmware.
See the troubleshooting suggestions for I cannot see or access the Login screen in the web configurator.
Ignore the suggestions about your browser.
36.3 Internet Access
I cannot access the Internet.
1Check the hardware connections, and make sure the LEDs are behaving as expected. See the Quick
Start Guide and Section 1.6.2 on page 20.
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2Make sure you entered your ISP account information correctly in the Network Setting > Broadband
screen. These fields are case-sensitive, so make sure [Caps Lock] is not on.
3If you are trying to access the Internet wirelessly, make sure that you enabled the wireless LAN in the
VMG and your wireless client and that the wireless settings in the wireless client are the same as the
settings in the VMG.
4Disconnect all the cables from your device and reconnect them.
5If the problem continues, contact your ISP.
I cannot access the Internet through a DSL connection.
1Make sure you have the DSL WAN port connected to a telephone jack (or the DSL or modem jack on a
splitter if you have one).
2Make sure you configured a proper DSL WAN interface (Network Setting > Broadband screen) with the
Internet account information provided by your ISP and that it is enabled.
3Check that the LAN interface you are connected to is in the same interface group as the DSL
connection (Network Setting > Interface Grouping).
4If you set up a WAN connection using bridging service, make sure you turn off the DHCP feature in the
LAN screen to have the clients get WAN IP addresses directly from your ISP’s DHCP server.
I cannot connect to the Internet using a second DSL connection.
ADSL and VDSL connections cannot work at the same time. You can only use one type of DSL
connection, either ADSL or VDSL connection at one time.
I cannot connect to the Internet using an Ethernet connection.
1Make sure you have the Ethernet WAN port connected to a Modem or Router.
2Make sure you configured a proper Ethernet WAN interface (Network Setting > Broadband screen) with
the Internet account information provided by your ISP and that it is enabled.
3Check that the WAN interface you are connected to is in the same interface group as the Ethernet
connection (Network Setting > Interface Grouping).
4If you set up a WAN connection using bridging service, make sure you turn off the DHCP feature in the
LAN screen to have the clients get WAN IP addresses directly from your ISP’s DHCP server.
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I cannot connect to the Internet using a cellular connection.
1The DSL and Ethernet WAN connections have priority in that order. If the DSL or Ethernet WAN
connection is up, then the cellular connection will be down.
2Make sure you have connected a compatible cellular dongle to the USB port.
3Make sure you have configured Network Setting > Broadband > Cellular Backup correctly.
4Check that the VMG is within range of a cellular base station.
I cannot access the VMG anymore. I had access to the VMG, but my connection is not available
anymore.
1Your session with the VMG may have expired. Try logging into the VMG again.
2Check the hardware connections, and make sure the LEDs are behaving as expected. See the Quick
Start Guide and Section 1.6.2 on page 20.
3Turn the VMG off and on.
4If the problem continues, contact your vendor.
36.4 Wireless Internet Access
What factors may cause intermittent or unstabled wireless connection? How can I solve this
problem?
The following factors may cause interference:
• Obstacles: walls, ceilings, furniture, and so on.
• Building Materials: metal doors, aluminum studs.
• Electrical devices: microwaves, monitors, electric motors, cordless phones, and other wireless devices.
To optimize the speed and quality of your wireless connection, you can:
• Move your wireless device closer to the AP if the signal strength is low.
• Reduce wireless interference that may be caused by other wireless networks or surrounding wireless
electronics such as cordless phones.
• Place the AP where there are minimum obstacles (such as walls and ceilings) between the AP and
the wireless client.
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• Reduce the number of wireless clients connecting to the same AP simultaneously, or add additional
APs if necessary.
• Try closing some programs that use the Internet, especially peer-to-peer applications. If the wireless
client is sending or receiving a lot of information, it may have too many programs open that use the
Internet.
What is a Server Set ID (SSID)?
An SSID is a name that uniquely identifies a wireless network. The AP and all the clients within a wireless
network must use the same SSID.
36.5 USB Device Connection
The VMG fails to detect my USB device.
1Disconnect the USB device.
2Reboot the VMG.
3If you are connecting a USB hard drive that comes with an external power supply, make sure it is
connected to an appropriate power source that is on.
4Re-connect your USB device to the VMG.
36.6 UPnP
When using UPnP and the VMG reboots, my computer cannot detect UPnP and refresh My
Network Places > Local Network.
1Disconnect the Ethernet cable from the VMG’s LAN port or from your computer.
2Re-connect the Ethernet cable.
The Local Area Connection icon for UPnP disappears in the screen.
Restart your computer.
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PART III
Appendices
Appendices contain general information. Some information may not apply to your device.
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APPENDIX A
Customer Support
In the event of problems that cannot be solved by using this manual, you should contact your vendor. If
you cannot contact your vendor, then contact a Zyxel office for the region in which you bought the
device.
See http://www.zyxel.com/homepage.shtml and also
http://www.zyxel.com/about_zyxel/zyxel_worldwide.shtml for the latest information.
Please have the following information ready when you contact an office.
Required Information
• Product model and serial number.
• Warranty Information.
• Date that you received your device.
• Brief description of the problem and the steps you took to solve it.
Corporate Headquarters (Worldwide)
Taiwan
• Zyxel Communications Corporation
• http://www.zyxel.com
Asia
China
• Zyxel Communications (Shanghai) Corp.
Zyxel Communications (Beijing) Corp.
Zyxel Communications (Tianjin) Corp.
• http://www.zyxel.cn
India
•Zyxel Technology India Pvt Ltd
• http://www.zyxel.in
Kazakhstan
•Zyxel Kazakhstan
• http://www.zyxel.kz
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Korea
• Zyxel Korea Corp.
• http://www.zyxel.kr
Malaysia
• Zyxel Malaysia Sdn Bhd.
• http://www.zyxel.com.my
Pakistan
• Zyxel Pakistan (Pvt.) Ltd.
• http://www.zyxel.com.pk
Philippines
• Zyxel Philippines
• http://www.zyxel.com.ph
Singapore
• Zyxel Singapore Pte Ltd.
• http://www.zyxel.com.sg
Taiwan
• Zyxel Communications Corporation
• http://www.zyxel.com/tw/zh/
Thailand
• Zyxel Thailand Co., Ltd
• http://www.zyxel.co.th
Vietnam
• Zyxel Communications Corporation-Vietnam Office
• http://www.zyxel.com/vn/vi
Europe
Austria
•Zyxel Deutschland GmbH
• http://www.zyxel.de
Belarus
•Zyxel BY
• http://www.zyxel.by
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Belgium
• Zyxel Communications B.V.
• http://www.zyxel.com/be/nl/
• http://www.zyxel.com/be/fr/
Bulgaria
•Zyxel България
• http://www.zyxel.com/bg/bg/
Czech Republic
• Zyxel Communications Czech s.r.o
• http://www.zyxel.cz
Denmark
• Zyxel Communications A/S
• http://www.zyxel.dk
Estonia
• Zyxel Estonia
• http://www.zyxel.com/ee/et/
Finland
• Zyxel Communications
• http://www.zyxel.fi
France
•Zyxel France
• http://www.zyxel.fr
Germany
•Zyxel Deutschland GmbH
• http://www.zyxel.de
Hungary
• Zyxel Hungary & SEE
• http://www.zyxel.hu
Italy
• Zyxel Communications Italy
• http://www.zyxel.it/
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Latvia
•Zyxel Latvia
• http://www.zyxel.com/lv/lv/homepage.shtml
Lithuania
•Zyxel Lithuania
• http://www.zyxel.com/lt/lt/homepage.shtml
Netherlands
• Zyxel Benelux
• http://www.zyxel.nl
Norway
• Zyxel Communications
• http://www.zyxel.no
Poland
• Zyxel Communications Poland
• http://www.zyxel.pl
Romania
• Zyxel Romania
• http://www.zyxel.com/ro/ro
Russia
• Zyxel Russia
• http://www.zyxel.ru
Slovakia
• Zyxel Communications Czech s.r.o. organizacna zlozka
• http://www.zyxel.sk
Spain
• Zyxel Communications ES Ltd
• http://www.zyxel.es
Sweden
• Zyxel Communications
• http://www.zyxel.se
Switzerland
•Studerus AG
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• http://www.zyxel.ch/
Turkey
• Zyxel Turkey A.S.
• http://www.zyxel.com.tr
UK
• Zyxel Communications UK Ltd.
• http://www.zyxel.co.uk
Ukraine
•Zyxel Ukraine
• http://www.ua.zyxel.com
Latin America
Argentina
• Zyxel Communication Corporation
• http://www.zyxel.com/ec/es/
Brazil
• Zyxel Communications Brasil Ltda.
• https://www.zyxel.com/br/pt/
Ecuador
• Zyxel Communication Corporation
• http://www.zyxel.com/ec/es/
Middle East
Israel
• Zyxel Communication Corporation
• http://il.zyxel.com/homepage.shtml
Middle East
• Zyxel Communication Corporation
• http://www.zyxel.com/me/en/
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North America
USA
• Zyxel Communications, Inc. - North America Headquarters
• http://www.zyxel.com/us/en/
Oceania
Australia
• Zyxel Communications Corporation
• http://www.zyxel.com/au/en/
Africa
South Africa
• Nology (Pty) Ltd.
• http://www.zyxel.co.za
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APPENDIX B
Wireless LANs
Wireless LAN Topologies
This section discusses ad-hoc and infrastructure wireless LAN topologies.
Ad-hoc Wireless LAN Configuration
The simplest WLAN configuration is an independent (Ad-hoc) WLAN that connects a set of computers
with wireless adapters (A, B, C). Any time two or more wireless adapters are within range of each other,
they can set up an independent network, which is commonly referred to as an ad-hoc network or
Independent Basic Service Set (IBSS). The following diagram shows an example of notebook computers
using wireless adapters to form an ad-hoc wireless LAN.
Figure 161 Peer-to-Peer Communication in an Ad-hoc Network
BSS
A Basic Service Set (BSS) exists when all communications between wireless clients or between a wireless
client and a wired network client go through one access point (AP).
Intra-BSS traffic is traffic between wireless clients in the BSS. When Intra-BSS is enabled, wireless client A
and B can access the wired network and communicate with each other. When Intra-BSS is disabled,
wireless client A and B can still access the wired network but cannot communicate with each other.
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Figure 162 Basic Service Set
ESS
An Extended Service Set (ESS) consists of a series of overlapping BSSs, each containing an access point,
with each access point connected together by a wired network. This wired connection between APs is
called a Distribution System (DS).
This type of wireless LAN topology is called an Infrastructure WLAN. The Access Points not only provide
communication with the wired network but also mediate wireless network traffic in the immediate
neighborhood.
An ESSID (ESS IDentification) uniquely identifies each ESS. All access points and their associated wireless
clients within the same ESS must have the same ESSID in order to communicate.
DSL
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Figure 163 Infrastructure WLAN
Channel
A channel is the radio frequency(ies) used by wireless devices to transmit and receive data. Channels
available depend on your geographical area. You may have a choice of channels (for your region) so
you should use a channel different from an adjacent AP (access point) to reduce interference.
Interference occurs when radio signals from different access points overlap causing interference and
degrading performance.
Adjacent channels partially overlap however. To avoid interference due to overlap, your AP should be
on a channel at least five channels away from a channel that an adjacent AP is using. For example, if
your region has 11 channels and an adjacent AP is using channel 1, then you need to select a channel
between 6 or 11.
RTS/CTS
A hidden node occurs when two stations are within range of the same access point, but are not within
range of each other. The following figure illustrates a hidden node. Both stations (STA) are within range
of the access point (AP) or wireless gateway, but out-of-range of each other, so they cannot "hear"
each other, that is they do not know if the channel is currently being used. Therefore, they are
considered hidden from each other.
DSL DSL
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Figure 164 RTS/CTS
When station A sends data to the AP, it might not know that the station B is already using the channel. If
these two stations send data at the same time, collisions may occur when both sets of data arrive at the
AP at the same time, resulting in a loss of messages for both stations.
RTS/CTS is designed to prevent collisions due to hidden nodes. An RTS/CTS defines the biggest size data
frame you can send before an RTS (Request To Send)/CTS (Clear to Send) handshake is invoked.
When a data frame exceeds the RTS/CTS value you set (between 0 to 2432 bytes), the station that wants
to transmit this frame must first send an RTS (Request To Send) message to the AP for permission to send
it. The AP then responds with a CTS (Clear to Send) message to all other stations within its range to notify
them to defer their transmission. It also reserves and confirms with the requesting station the time frame
for the requested transmission.
Stations can send frames smaller than the specified RTS/CTS directly to the AP without the RTS (Request
To Send)/CTS (Clear to Send) handshake.
You should only configure RTS/CTS if the possibility of hidden nodes exists on your network and the "cost"
of resending large frames is more than the extra network overhead involved in the RTS (Request To
Send)/CTS (Clear to Send) handshake.
If the RTS/CTS value is greater than the Fragmentation Threshold value (see next), then the RTS (Request
To Send)/CTS (Clear to Send) handshake will never occur as data frames will be fragmented before
they reach RTS/CTS size.
Note: Enabling the RTS Threshold causes redundant network overhead that could negatively
affect the throughput performance instead of providing a remedy.
Fragmentation Threshold
A Fragmentation Threshold is the maximum data fragment size (between 256 and 2432 bytes) that can
be sent in the wireless network before the AP will fragment the packet into smaller data frames.
A large Fragmentation Threshold is recommended for networks not prone to interference while you
should set a smaller threshold for busy networks or networks that are prone to interference.
DSL
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If the Fragmentation Threshold value is smaller than the RTS/CTS value (see previously) you set then the
RTS (Request To Send)/CTS (Clear to Send) handshake will never occur as data frames will be
fragmented before they reach RTS/CTS size.
IEEE 802.11g Wireless LAN
IEEE 802.11g is fully compatible with the IEEE 802.11b standard. This means an IEEE 802.11b adapter can
interface directly with an IEEE 802.11g access point (and vice versa) at 11 Mbps or lower depending on
range. IEEE 802.11g has several intermediate rate steps between the maximum and minimum data
rates. The IEEE 802.11g data rate and modulation are as follows:
Wireless Security Overview
Wireless security is vital to your network to protect wireless communication between wireless clients,
access points and the wired network.
Wireless security methods available on the VMG are data encryption, wireless client authentication,
restricting access by device MAC address and hiding the VMG identity.
The following figure shows the relative effectiveness of these wireless security methods available on your
VMG.
Note: You must enable the same wireless security settings on the VMG and on all wireless
clients that you want to associate with it.
IEEE 802.1x
In June 2001, the IEEE 802.1x standard was designed to extend the features of IEEE 802.11 to support
extended authentication as well as providing additional accounting and control features. It is
supported by Windows XP and a number of network devices. Some advantages of IEEE 802.1x are:
Table 121 IEEE 802.11g
DATA RATE (MBPS) MODULATION
1 DBPSK (Differential Binary Phase Shift Keyed)
2 DQPSK (Differential Quadrature Phase Shift Keying)
5.5 / 11 CCK (Complementary Code Keying)
6/9/12/18/24/36/48/54 OFDM (Orthogonal Frequency Division Multiplexing)
Table 122 Wireless Security Levels
SECURITY
LEVEL SECURITY TYPE
Least Secure
Most Secure
Unique SSID (Default)
Unique SSID with Hide SSID Enabled
MAC Address Filtering
WEP Encryption
IEEE802.1x EAP with RADIUS Server Authentication
Wi-Fi Protected Access (WPA)
WPA2
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• User based identification that allows for roaming.
• Support for RADIUS (Remote Authentication Dial In User Service, RFC 2138, 2139) for centralized user
profile and accounting management on a network RADIUS server.
• Support for EAP (Extensible Authentication Protocol, RFC 2486) that allows additional authentication
methods to be deployed with no changes to the access point or the wireless clients.
RADIUS
RADIUS is based on a client-server model that supports authentication, authorization and accounting.
The access point is the client and the server is the RADIUS server. The RADIUS server handles the following
tasks:
• Authentication
Determines the identity of the users.
•Authorization
Determines the network services available to authenticated users once they are connected to the
network.
• Accounting
Keeps track of the client’s network activity.
RADIUS is a simple package exchange in which your AP acts as a message relay between the wireless
client and the network RADIUS server.
Types of RADIUS Messages
The following types of RADIUS messages are exchanged between the access point and the RADIUS
server for user authentication:
• Access-Request
Sent by an access point requesting authentication.
• Access-Reject
Sent by a RADIUS server rejecting access.
• Access-Accept
Sent by a RADIUS server allowing access.
• Access-Challenge
Sent by a RADIUS server requesting more information in order to allow access. The access point sends
a proper response from the user and then sends another Access-Request message.
The following types of RADIUS messages are exchanged between the access point and the RADIUS
server for user accounting:
• Accounting-Request
Sent by the access point requesting accounting.
• Accounting-Response
Sent by the RADIUS server to indicate that it has started or stopped accounting.
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In order to ensure network security, the access point and the RADIUS server use a shared secret key,
which is a password, they both know. The key is not sent over the network. In addition to the shared key,
password information exchanged is also encrypted to protect the network from unauthorized access.
Types of EAP Authentication
This section discusses some popular authentication types: EAP-MD5, EAP-TLS, EAP-TTLS, PEAP and LEAP.
Your wireless LAN device may not support all authentication types.
EAP (Extensible Authentication Protocol) is an authentication protocol that runs on top of the IEEE 802.1x
transport mechanism in order to support multiple types of user authentication. By using EAP to interact
with an EAP-compatible RADIUS server, an access point helps a wireless station and a RADIUS server
perform authentication.
The type of authentication you use depends on the RADIUS server and an intermediary AP(s) that
supports IEEE 802.1x.
For EAP-TLS authentication type, you must first have a wired connection to the network and obtain the
certificate(s) from a certificate authority (CA). A certificate (also called digital IDs) can be used to
authenticate users and a CA issues certificates and guarantees the identity of each certificate owner.
EAP-MD5 (Message-Digest Algorithm 5)
MD5 authentication is the simplest one-way authentication method. The authentication server sends a
challenge to the wireless client. The wireless client ‘proves’ that it knows the password by encrypting the
password with the challenge and sends back the information. Password is not sent in plain text.
However, MD5 authentication has some weaknesses. Since the authentication server needs to get the
plaintext passwords, the passwords must be stored. Thus someone other than the authentication server
may access the password file. In addition, it is possible to impersonate an authentication server as MD5
authentication method does not perform mutual authentication. Finally, MD5 authentication method
does not support data encryption with dynamic session key. You must configure WEP encryption keys for
data encryption.
EAP-TLS (Transport Layer Security)
With EAP-TLS, digital certifications are needed by both the server and the wireless clients for mutual
authentication. The server presents a certificate to the client. After validating the identity of the server,
the client sends a different certificate to the server. The exchange of certificates is done in the open
before a secured tunnel is created. This makes user identity vulnerable to passive attacks. A digital
certificate is an electronic ID card that authenticates the sender’s identity. However, to implement EAP-
TLS, you need a Certificate Authority (CA) to handle certificates, which imposes a management
overhead.
EAP-TTLS (Tunneled Transport Layer Service)
EAP-TTLS is an extension of the EAP-TLS authentication that uses certificates for only the server-side
authentications to establish a secure connection. Client authentication is then done by sending
username and password through the secure connection, thus client identity is protected. For client
authentication, EAP-TTLS supports EAP methods and legacy authentication methods such as PAP, CHAP,
MS-CHAP and MS-CHAP v2.
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PEAP (Protected EAP)
Like EAP-TTLS, server-side certificate authentication is used to establish a secure connection, then use
simple username and password methods through the secured connection to authenticate the clients,
thus hiding client identity. However, PEAP only supports EAP methods, such as EAP-MD5, EAP-MSCHAPv2
and EAP-GTC (EAP-Generic Token Card), for client authentication. EAP-GTC is implemented only by
Cisco.
LEAP
LEAP (Lightweight Extensible Authentication Protocol) is a Cisco implementation of IEEE 802.1x.
Dynamic WEP Key Exchange
The AP maps a unique key that is generated with the RADIUS server. This key expires when the wireless
connection times out, disconnects or reauthentication times out. A new WEP key is generated each
time reauthentication is performed.
If this feature is enabled, it is not necessary to configure a default encryption key in the wireless security
configuration screen. You may still configure and store keys, but they will not be used while dynamic
WEP is enabled.
Note: EAP-MD5 cannot be used with Dynamic WEP Key Exchange
For added security, certificate-based authentications (EAP-TLS, EAP-TTLS and PEAP) use dynamic keys for
data encryption. They are often deployed in corporate environments, but for public deployment, a
simple user name and password pair is more practical. The following table is a comparison of the
features of authentication types.
WPA and WPA2
Wi-Fi Protected Access (WPA) is a subset of the IEEE 802.11i standard. WPA2 (IEEE 802.11i) is a wireless
security standard that defines stronger encryption, authentication and key management than WPA.
Key differences between WPA or WPA2 and WEP are improved data encryption and user
authentication.
If both an AP and the wireless clients support WPA2 and you have an external RADIUS server, use WPA2
for stronger data encryption. If you don't have an external RADIUS server, you should use WPA2-PSK
(WPA2-Pre-Shared Key) that only requires a single (identical) password entered into each access point,
Table 123 Comparison of EAP Authentication Types
EAP-MD5 EAP-TLS EAP-TTLS PEAP LEAP
Mutual Authentication No Yes Yes Yes Yes
Certificate – Client No Yes Optional Optional No
Certificate – Server No Yes Yes Yes No
Dynamic Key Exchange No Yes Yes Yes Yes
Credential Integrity None Strong Strong Strong Moderate
Deployment Difficulty Easy Hard Moderate Moderate Moderate
Client Identity Protection No No Yes Yes No
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wireless gateway and wireless client. As long as the passwords match, a wireless client will be granted
access to a WLAN.
If the AP or the wireless clients do not support WPA2, just use WPA or WPA-PSK depending on whether
you have an external RADIUS server or not.
Select WEP only when the AP and/or wireless clients do not support WPA or WPA2. WEP is less secure
than WPA or WPA2.
Encryption
WPA improves data encryption by using Temporal Key Integrity Protocol (TKIP), Message Integrity Check
(MIC) and IEEE 802.1x. WPA2 also uses TKIP when required for compatibility reasons, but offers stronger
encryption than TKIP with Advanced Encryption Standard (AES) in the Counter mode with Cipher block
chaining Message authentication code Protocol (CCMP).
TKIP uses 128-bit keys that are dynamically generated and distributed by the authentication server. AES
(Advanced Encryption Standard) is a block cipher that uses a 256-bit mathematical algorithm called
Rijndael. They both include a per-packet key mixing function, a Message Integrity Check (MIC) named
Michael, an extended initialization vector (IV) with sequencing rules, and a re-keying mechanism.
WPA and WPA2 regularly change and rotate the encryption keys so that the same encryption key is
never used twice.
The RADIUS server distributes a Pairwise Master Key (PMK) key to the AP that then sets up a key hierarchy
and management system, using the PMK to dynamically generate unique data encryption keys to
encrypt every data packet that is wirelessly communicated between the AP and the wireless clients. This
all happens in the background automatically.
The Message Integrity Check (MIC) is designed to prevent an attacker from capturing data packets,
altering them and resending them. The MIC provides a strong mathematical function in which the
receiver and the transmitter each compute and then compare the MIC. If they do not match, it is
assumed that the data has been tampered with and the packet is dropped.
By generating unique data encryption keys for every data packet and by creating an integrity
checking mechanism (MIC), with TKIP and AES it is more difficult to decrypt data on a Wi-Fi network than
WEP and difficult for an intruder to break into the network.
The encryption mechanisms used for WPA(2) and WPA(2)-PSK are the same. The only difference
between the two is that WPA(2)-PSK uses a simple common password, instead of user-specific
credentials. The common-password approach makes WPA(2)-PSK susceptible to brute-force password-
guessing attacks but it’s still an improvement over WEP as it employs a consistent, single, alphanumeric
password to derive a PMK which is used to generate unique temporal encryption keys. This prevent all
wireless devices sharing the same encryption keys. (a weakness of WEP)
User Authentication
WPA and WPA2 apply IEEE 802.1x and Extensible Authentication Protocol (EAP) to authenticate wireless
clients using an external RADIUS database. WPA2 reduces the number of key exchange messages from
six to four (CCMP 4-way handshake) and shortens the time required to connect to a network. Other
WPA2 authentication features that are different from WPA include key caching and pre-authentication.
These two features are optional and may not be supported in all wireless devices.
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Key caching allows a wireless client to store the PMK it derived through a successful authentication with
an AP. The wireless client uses the PMK when it tries to connect to the same AP and does not need to go
with the authentication process again.
Pre-authentication enables fast roaming by allowing the wireless client (already connecting to an AP) to
perform IEEE 802.1x authentication with another AP before connecting to it.
Wireless Client WPA Supplicants
A wireless client supplicant is the software that runs on an operating system instructing the wireless client
how to use WPA. At the time of writing, the most widely available supplicant is the WPA patch for
Windows XP, Funk Software's Odyssey client.
The Windows XP patch is a free download that adds WPA capability to Windows XP's built-in "Zero
Configuration" wireless client. However, you must run Windows XP to use it.
WPA(2) with RADIUS Application Example
To set up WPA(2), you need the IP address of the RADIUS server, its port number (default is 1812), and the
RADIUS shared secret. A WPA(2) application example with an external RADIUS server looks as follows. "A"
is the RADIUS server. "DS" is the distribution system.
1The AP passes the wireless client's authentication request to the RADIUS server.
2The RADIUS server then checks the user's identification against its database and grants or denies
network access accordingly.
3A 256-bit Pairwise Master Key (PMK) is derived from the authentication process by the RADIUS server and
the client.
4The RADIUS server distributes the PMK to the AP. The AP then sets up a key hierarchy and management
system, using the PMK to dynamically generate unique data encryption keys. The keys are used to
encrypt every data packet that is wirelessly communicated between the AP and the wireless clients.
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Figure 165 WPA(2) with RADIUS Application Example
WPA(2)-PSK Application Example
A WPA(2)-PSK application looks as follows.
1First enter identical passwords into the AP and all wireless clients. The Pre-Shared Key (PSK) must consist
of between 8 and 63 ASCII characters or 64 hexadecimal characters (including spaces and symbols).
2The AP checks each wireless client's password and allows it to join the network only if the password
matches.
3The AP and wireless clients generate a common PMK (Pairwise Master Key). The key itself is not sent over
the network, but is derived from the PSK and the SSID.
4The AP and wireless clients use the TKIP or AES encryption process, the PMK and information exchanged
in a handshake to create temporal encryption keys. They use these keys to encrypt data exchanged
between them.
Figure 166 WPA(2)-PSK Authentication
A
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Security Parameters Summary
Refer to this table to see what other security parameters you should configure for each authentication
method or key management protocol type. MAC address filters are not dependent on how you
configure these security features.
Antenna Overview
An antenna couples RF signals onto air. A transmitter within a wireless device sends an RF signal to the
antenna, which propagates the signal through the air. The antenna also operates in reverse by
capturing RF signals from the air.
Positioning the antennas properly increases the range and coverage area of a wireless LAN.
Antenna Characteristics
Frequency
An antenna in the frequency of 2.4GHz (IEEE 802.11b and IEEE 802.11g) or 5GHz (IEEE 802.11a) is needed
to communicate efficiently in a wireless LAN
Radiation Pattern
A radiation pattern is a diagram that allows you to visualize the shape of the antenna’s coverage area.
Antenna Gain
Antenna gain, measured in dB (decibel), is the increase in coverage within the RF beam width. Higher
antenna gain improves the range of the signal for better communications.
For an indoor site, each 1 dB increase in antenna gain results in a range increase of approximately 2.5%.
For an unobstructed outdoor site, each 1dB increase in gain results in a range increase of approximately
Table 124 Wireless Security Relational Matrix
AUTHENTICATION METHOD/
KEY MANAGEMENT
PROTOCOL
ENCRYPTION
METHOD ENTER MANUAL
KEY IEEE 802.1X
Open None No Disable
Enable without Dynamic WEP Key
Open WEP No Enable with Dynamic WEP Key
Yes Enable without Dynamic WEP Key
Yes Disable
Shared WEP No Enable with Dynamic WEP Key
Yes Enable without Dynamic WEP Key
Yes Disable
WPA TKIP/AES No Enable
WPA-PSK TKIP/AES Yes Disable
WPA2 TKIP/AES No Enable
WPA2-PSK TKIP/AES Yes Disable
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5%. Actual results may vary depending on the network environment.
Antenna gain is sometimes specified in dBi, which is how much the antenna increases the signal power
compared to using an isotropic antenna. An isotropic antenna is a theoretical perfect antenna that
sends out radio signals equally well in all directions. dBi represents the true gain that the antenna
provides.
Types of Antennas for WLAN
There are two types of antennas used for wireless LAN applications.
• Omni-directional antennas send the RF signal out in all directions on a horizontal plane. The coverage
area is torus-shaped (like a donut) which makes these antennas ideal for a room environment. With a
wide coverage area, it is possible to make circular overlapping coverage areas with multiple access
points.
• Directional antennas concentrate the RF signal in a beam, like a flashlight does with the light from its
bulb. The angle of the beam determines the width of the coverage pattern. Angles typically range
from 20 degrees (very directional) to 120 degrees (less directional). Directional antennas are ideal for
hallways and outdoor point-to-point applications.
Positioning Antennas
In general, antennas should be mounted as high as practically possible and free of obstructions. In
point-to–point application, position both antennas at the same height and in a direct line of sight to
each other to attain the best performance.
For omni-directional antennas mounted on a table, desk, and so on, point the antenna up. For omni-
directional antennas mounted on a wall or ceiling, point the antenna down. For a single AP application,
place omni-directional antennas as close to the center of the coverage area as possible.
For directional antennas, point the antenna in the direction of the desired coverage area.
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APPENDIX C
IPv6
Overview
IPv6 (Internet Protocol version 6), is designed to enhance IP address size and features. The increase in
IPv6 address size to 128 bits (from the 32-bit IPv4 address) allows up to 3.4 x 1038 IP addresses.
IPv6 Addressing
The 128-bit IPv6 address is written as eight 16-bit hexadecimal blocks separated by colons (:). This is an
example IPv6 address 2001:0db8:1a2b:0015:0000:0000:1a2f:0000.
IPv6 addresses can be abbreviated in two ways:
• Leading zeros in a block can be omitted. So 2001:0db8:1a2b:0015:0000:0000:1a2f:0000 can be
written as 2001:db8:1a2b:15:0:0:1a2f:0.
• Any number of consecutive blocks of zeros can be replaced by a double colon. A double colon can
only appear once in an IPv6 address. So 2001:0db8:0000:0000:1a2f:0000:0000:0015 can be
written as 2001:0db8::1a2f:0000:0000:0015, 2001:0db8:0000:0000:1a2f::0015,
2001:db8::1a2f:0:0:15 or 2001:db8:0:0:1a2f::15.
Prefix and Prefix Length
Similar to an IPv4 subnet mask, IPv6 uses an address prefix to represent the network address. An IPv6
prefix length specifies how many most significant bits (start from the left) in the address compose the
network address. The prefix length is written as “/x” where x is a number. For example,
2001:db8:1a2b:15::1a2f:0/32
means that the first 32 bits (2001:db8) is the subnet prefix.
Link-local Address
A link-local address uniquely identifies a device on the local network (the LAN). It is similar to a “private IP
address” in IPv4. You can have the same link-local address on multiple interfaces on a device. A link-
local unicast address has a predefined prefix of fe80::/10. The link-local unicast address format is as
follows.
Table 125 Link-local Unicast Address Format
Global Address
A global address uniquely identifies a device on the Internet. It is similar to a “public IP address” in IPv4. A
global unicast address starts with a 2 or 3.
1111 1110 10 0 Interface ID
10 bits 54 bits 64 bits
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Unspecified Address
An unspecified address (0:0:0:0:0:0:0:0 or ::) is used as the source address when a device does not have
its own address. It is similar to “0.0.0.0” in IPv4.
Loopback Address
A loopback address (0:0:0:0:0:0:0:1 or ::1) allows a host to send packets to itself. It is similar to “127.0.0.1”
in IPv4.
Multicast Address
In IPv6, multicast addresses provide the same functionality as IPv4 broadcast addresses. Broadcasting is
not supported in IPv6. A multicast address allows a host to send packets to all hosts in a multicast group.
Multicast scope allows you to determine the size of the multicast group. A multicast address has a
predefined prefix of ff00::/8. The following table describes some of the predefined multicast addresses.
The following table describes the multicast addresses which are reserved and can not be assigned to a
multicast group.
Table 126 Predefined Multicast Address
MULTICAST ADDRESS DESCRIPTION
FF01:0:0:0:0:0:0:1 All hosts on a local node.
FF01:0:0:0:0:0:0:2 All routers on a local node.
FF02:0:0:0:0:0:0:1 All hosts on a local connected link.
FF02:0:0:0:0:0:0:2 All routers on a local connected link.
FF05:0:0:0:0:0:0:2 All routers on a local site.
FF05:0:0:0:0:0:1:3 All DHCP severs on a local site.
Table 127 Reserved Multicast Address
MULTICAST ADDRESS
FF00:0:0:0:0:0:0:0
FF01:0:0:0:0:0:0:0
FF02:0:0:0:0:0:0:0
FF03:0:0:0:0:0:0:0
FF04:0:0:0:0:0:0:0
FF05:0:0:0:0:0:0:0
FF06:0:0:0:0:0:0:0
FF07:0:0:0:0:0:0:0
FF08:0:0:0:0:0:0:0
FF09:0:0:0:0:0:0:0
FF0A:0:0:0:0:0:0:0
FF0B:0:0:0:0:0:0:0
FF0C:0:0:0:0:0:0:0
FF0D:0:0:0:0:0:0:0
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Subnet Masking
Both an IPv6 address and IPv6 subnet mask compose of 128-bit binary digits, which are divided into
eight 16-bit blocks and written in hexadecimal notation. Hexadecimal uses four bits for each character
(1 ~ 10, A ~ F). Each block’s 16 bits are then represented by four hexadecimal characters. For example,
FFFF:FFFF:FFFF:FFFF:FC00:0000:0000:0000.
Interface ID
In IPv6, an interface ID is a 64-bit identifier. It identifies a physical interface (for example, an Ethernet
port) or a virtual interface (for example, the management IP address for a VLAN). One interface should
have a unique interface ID.
EUI-64
The EUI-64 (Extended Unique Identifier) defined by the IEEE (Institute of Electrical and Electronics
Engineers) is an interface ID format designed to adapt with IPv6. It is derived from the 48-bit (6-byte)
Ethernet MAC address as shown next. EUI-64 inserts the hex digits fffe between the third and fourth bytes
of the MAC address and complements the seventh bit of the first byte of the MAC address. See the
following example.
Identity Association
An Identity Association (IA) is a collection of addresses assigned to a DHCP client, through which the
server and client can manage a set of related IP addresses. Each IA must be associated with exactly
one interface. The DHCP client uses the IA assigned to an interface to obtain configuration from a DHCP
server for that interface. Each IA consists of a unique IAID and associated IP information.
The IA type is the type of address in the IA. Each IA holds one type of address. IA_NA means an identity
association for non-temporary addresses and IA_TA is an identity association for temporary addresses.
An IA_NA option contains the T1 and T2 fields, but an IA_TA option does not. The DHCPv6 server uses T1
and T2 to control the time at which the client contacts with the server to extend the lifetimes on any
addresses in the IA_NA before the lifetimes expire. After T1, the client sends the server (S1) (from which
the addresses in the IA_NA were obtained) a Renew message. If the time T2 is reached and the server
FF0E:0:0:0:0:0:0:0
FF0F:0:0:0:0:0:0:0
Table 127 Reserved Multicast Address (continued)
MULTICAST ADDRESS
MAC 00 : 13 : 49 :12 : 34 :56
EUI-64 02:13 :49 :FF :FE :12 : 34 :56
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does not respond, the client sends a Rebind message to any available server (S2). For an IA_TA, the
client may send a Renew or Rebind message at the client's discretion.
DHCP Relay Agent
A DHCP relay agent is on the same network as the DHCP clients and helps forward messages between
the DHCP server and clients. When a client cannot use its link-local address and a well-known multicast
address to locate a DHCP server on its network, it then needs a DHCP relay agent to send a message to
a DHCP server that is not attached to the same network.
The DHCP relay agent can add the remote identification (remote-ID) option and the interface-ID option
to the Relay-Forward DHCPv6 messages. The remote-ID option carries a user-defined string, such as the
system name. The interface-ID option provides slot number, port information and the VLAN ID to the
DHCPv6 server. The remote-ID option (if any) is stripped from the Relay-Reply messages before the relay
agent sends the packets to the clients. The DHCP server copies the interface-ID option from the Relay-
Forward message into the Relay-Reply message and sends it to the relay agent. The interface-ID should
not change even after the relay agent restarts.
Prefix Delegation
Prefix delegation enables an IPv6 router to use the IPv6 prefix (network address) received from the ISP (or
a connected uplink router) for its LAN. The VMG uses the received IPv6 prefix (for example, 2001:db2::/
48) to generate its LAN IP address. Through sending Router Advertisements (RAs) regularly by multicast,
the VMG passes the IPv6 prefix information to its LAN hosts. The hosts then can use the prefix to generate
their IPv6 addresses.
ICMPv6
Internet Control Message Protocol for IPv6 (ICMPv6 or ICMP for IPv6) is defined in RFC 4443. ICMPv6 has
a preceding Next Header value of 58, which is different from the value used to identify ICMP for IPv4.
ICMPv6 is an integral part of IPv6. IPv6 nodes use ICMPv6 to report errors encountered in packet
processing and perform other diagnostic functions, such as "ping".
Neighbor Discovery Protocol (NDP)
The Neighbor Discovery Protocol (NDP) is a protocol used to discover other IPv6 devices and track
neighbor’s reachability in a network. An IPv6 device uses the following ICMPv6 messages types:
• Neighbor solicitation: A request from a host to determine a neighbor’s link-layer address (MAC
address) and detect if the neighbor is still reachable. A neighbor being “reachable” means it
responds to a neighbor solicitation message (from the host) with a neighbor advertisement message.
• Neighbor advertisement: A response from a node to announce its link-layer address.
T1
T2
Renew Rebind
Rebind
to S1
Renew
to S1
Renew
to S1
Renew
to S1
Renew
to S1
Renew
to S1
to S2
to S2
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• Router solicitation: A request from a host to locate a router that can act as the default router and
forward packets.
• Router advertisement: A response to a router solicitation or a periodical multicast advertisement from
a router to advertise its presence and other parameters.
IPv6 Cache
An IPv6 host is required to have a neighbor cache, destination cache, prefix list and default router list.
The VMG maintains and updates its IPv6 caches constantly using the information from response
messages. In IPv6, the VMG configures a link-local address automatically, and then sends a neighbor
solicitation message to check if the address is unique. If there is an address to be resolved or verified, the
VMG also sends out a neighbor solicitation message. When the VMG receives a neighbor
advertisement in response, it stores the neighbor’s link-layer address in the neighbor cache. When the
VMG uses a router solicitation message to query for a router and receives a router advertisement
message, it adds the router’s information to the neighbor cache, prefix list and destination cache. The
VMG creates an entry in the default router list cache if the router can be used as a default router.
When the VMG needs to send a packet, it first consults the destination cache to determine the next
hop. If there is no matching entry in the destination cache, the VMG uses the prefix list to determine
whether the destination address is on-link and can be reached directly without passing through a router.
If the address is unlink, the address is considered as the next hop. Otherwise, the VMG determines the
next-hop from the default router list or routing table. Once the next hop IP address is known, the VMG
looks into the neighbor cache to get the link-layer address and sends the packet when the neighbor is
reachable. If the VMG cannot find an entry in the neighbor cache or the state for the neighbor is not
reachable, it starts the address resolution process. This helps reduce the number of IPv6 solicitation and
advertisement messages.
Multicast Listener Discovery
The Multicast Listener Discovery (MLD) protocol (defined in RFC 2710) is derived from IPv4's Internet
Group Management Protocol version 2 (IGMPv2). MLD uses ICMPv6 message types, rather than IGMP
message types. MLDv1 is equivalent to IGMPv2 and MLDv2 is equivalent to IGMPv3.
MLD allows an IPv6 switch or router to discover the presence of MLD listeners who wish to receive
multicast packets and the IP addresses of multicast groups the hosts want to join on its network.
MLD snooping and MLD proxy are analogous to IGMP snooping and IGMP proxy in IPv4.
MLD filtering controls which multicast groups a port can join.
MLD Messages
A multicast router or switch periodically sends general queries to MLD hosts to update the multicast
forwarding table. When an MLD host wants to join a multicast group, it sends an MLD Report message
for that address.
An MLD Done message is equivalent to an IGMP Leave message. When an MLD host wants to leave a
multicast group, it can send a Done message to the router or switch. The router or switch then sends a
group-specific query to the port on which the Done message is received to determine if other devices
connected to this port should remain in the group.
Appendix C IPv6
VMG3312-T20A User’s Guide
284
Example - Enabling IPv6 on Windows XP/2003/Vista
By default, Windows XP and Windows 2003 support IPv6. This example shows you how to use the ipv6
install command on Windows XP/2003 to enable IPv6. This also displays how to use the ipconfig
command to see auto-generated IP addresses.
IPv6 is installed and enabled by default in Windows Vista. Use the ipconfig command to check your
automatic configured IPv6 address as well. You should see at least one IPv6 address available for the
interface on your computer.
Example - Enabling DHCPv6 on Windows XP
Windows XP does not support DHCPv6. If your network uses DHCPv6 for IP address assignment, you have
to additionally install a DHCPv6 client software on your Windows XP. (Note: If you use static IP addresses
or Router Advertisement for IPv6 address assignment in your network, ignore this section.)
This example uses Dibbler as the DHCPv6 client. To enable DHCPv6 client on your computer:
1Install Dibbler and select the DHCPv6 client option on your computer.
2After the installation is complete, select Start > All Programs > Dibbler-DHCPv6 > Client Install as service.
3Select Start > Control Panel > Administrative Tools > Services.
4Double click Dibbler - a DHCPv6 client.
C:\>ipv6 install
Installing...
Succeeded.
C:\>ipconfig
Windows IP Configuration
Ethernet adapter Local Area Connection:
Connection-specific DNS Suffix . :
IP Address. . . . . . . . . . . . : 10.1.1.46
Subnet Mask . . . . . . . . . . . : 255.255.255.0
IP Address. . . . . . . . . . . . : fe80::2d0:59ff:feb8:103c%4
Default Gateway . . . . . . . . . : 10.1.1.254
Appendix C IPv6
VMG3312-T20A User’s Guide
285
5Click Start and then OK.
6Now your computer can obtain an IPv6 address from a DHCPv6 server.
Example - Enabling IPv6 on Windows 7
Windows 7 supports IPv6 by default. DHCPv6 is also enabled when you enable IPv6 on a Windows 7
computer.
To enable IPv6 in Windows 7:
1Select Control Panel > Network and Sharing Center > Local Area Connection.
2Select the Internet Protocol Version 6 (TCP/IPv6) checkbox to enable it.
3Click OK to save the change.
Appendix C IPv6
VMG3312-T20A User’s Guide
286
4Click Close to exit the Local Area Connection Status screen.
5Select Start > All Programs > Accessories > Command Prompt.
6Use the ipconfig command to check your dynamic IPv6 address. This example shows a global address
(2001:b021:2d::1000) obtained from a DHCP server.
C:\>ipconfig
Windows IP Configuration
Ethernet adapter Local Area Connection:
Connection-specific DNS Suffix . :
IPv6 Address. . . . . . . . . . . : 2001:b021:2d::1000
Link-local IPv6 Address . . . . . : fe80::25d8:dcab:c80a:5189%11
IPv4 Address. . . . . . . . . . . : 172.16.100.61
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : fe80::213:49ff:feaa:7125%11
172.16.100.254
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287
APPENDIX D
Services
The following table lists some commonly-used services and their associated protocols and port numbers.
•Name: This is a short, descriptive name for the service. You can use this one or create a different one,
if you like.
•Protocol: This is the type of IP protocol used by the service. If this is TCP/UDP, then the service uses the
same port number with TCP and UDP. If this is USER-DEFINED, the Port(s) is the IP protocol number, not
the port number.
•Port(s): This value depends on the Protocol.
•If the Protocol is TCP, UDP, or TCP/UDP, this is the IP port number.
•If the Protocol is USER, this is the IP protocol number.
•Description: This is a brief explanation of the applications that use this service or the situations in which
this service is used.
Appendix D Services
VMG3312-T20A User’s Guide
288
Table 128 Examples of Services
NAME PROTOCOL PORT(S) DESCRIPTION
AH (IPSEC_TUNNEL) User-Defined 51 The IPSEC AH (Authentication Header) tunneling
protocol uses this service.
AIM TCP 5190 AOL’s Internet Messenger service.
AUTH TCP 113 Authentication protocol used by some servers.
BGP TCP 179 Border Gateway Protocol.
BOOTP_CLIENT UDP 68 DHCP Client.
BOOTP_SERVER UDP 67 DHCP Server.
CU-SEEME TCP/UDP
TCP/UDP
7648
24032
A popular videoconferencing solution from White
Pines Software.
DNS TCP/UDP 53 Domain Name Server, a service that matches web
names (for instance www.zyxel.com) to IP numbers.
ESP (IPSEC_TUNNEL) User-Defined 50 The IPSEC ESP (Encapsulation Security Protocol)
tunneling protocol uses this service.
FINGER TCP 79 Finger is a UNIX or Internet related command that can
be used to find out if a user is logged on.
FTP TCP
TCP
20
21
File Transfer Protocol, a program to enable fast
transfer of files, including large files that may not be
possible by e-mail.
H.323 TCP 1720 NetMeeting uses this protocol.
HTTP TCP 80 Hyper Text Transfer Protocol - a client/server protocol
for the world wide web.
HTTPS TCP 443 HTTPS is a secured http session often used in e-
commerce.
ICMP User-Defined 1Internet Control Message Protocol is often used for
diagnostic purposes.
ICQ UDP 4000 This is a popular Internet chat program.
IGMP (MULTICAST) User-Defined 2Internet Group Multicast Protocol is used when
sending packets to a specific group of hosts.
IKE UDP 500 The Internet Key Exchange algorithm is used for key
distribution and management.
IMAP4 TCP 143 The Internet Message Access Protocol is used for e-
mail.
IMAP4S TCP 993 This is a more secure version of IMAP4 that runs over
SSL.
IRC TCP/UDP 6667 This is another popular Internet chat program.
MSN Messenger TCP 1863 Microsoft Networks’ messenger service uses this
protocol.
NetBIOS TCP/UDP
TCP/UDP
TCP/UDP
TCP/UDP
137
138
139
445
The Network Basic Input/Output System is used for
communication between computers in a LAN.
NEW-ICQ TCP 5190 An Internet chat program.
NEWS TCP 144 A protocol for news groups.
Appendix D Services
VMG3312-T20A User’s Guide
289
NFS UDP 2049 Network File System - NFS is a client/server distributed
file service that provides transparent file sharing for
network environments.
NNTP TCP 119 Network News Transport Protocol is the delivery
mechanism for the USENET newsgroup service.
PING User-Defined 1Packet INternet Groper is a protocol that sends out
ICMP echo requests to test whether or not a remote
host is reachable.
POP3 TCP 110 Post Office Protocol version 3 lets a client computer
get e-mail from a POP3 server through a temporary
connection (TCP/IP or other).
POP3S TCP 995 This is a more secure version of POP3 that runs over
SSL.
PPTP TCP 1723 Point-to-Point Tunneling Protocol enables secure
transfer of data over public networks. This is the
control channel.
PPTP_TUNNEL (GRE) User-Defined 47 PPTP (Point-to-Point Tunneling Protocol) enables
secure transfer of data over public networks. This is the
data channel.
RCMD TCP 512 Remote Command Service.
REAL_AUDIO TCP 7070 A streaming audio service that enables real time
sound over the web.
REXEC TCP 514 Remote Execution Daemon.
RLOGIN TCP 513 Remote Login.
ROADRUNNER TCP/UDP 1026 This is an ISP that provides services mainly for cable
modems.
RTELNET TCP 107 Remote Telnet.
RTSP TCP/UDP 554 The Real Time Streaming (media control) Protocol
(RTSP) is a remote control for multimedia on the
Internet.
SFTP TCP 115 The Simple File Transfer Protocol is an old way of
transferring files between computers.
SMTP TCP 25 Simple Mail Transfer Protocol is the message-
exchange standard for the Internet. SMTP enables
you to move messages from one e-mail server to
another.
SMTPS TCP 465 This is a more secure version of SMTP that runs over SSL.
SNMP TCP/UDP 161 Simple Network Management Program.
SNMP-TRAPS TCP/UDP 162 Traps for use with the SNMP (RFC:1215).
SQL-NET TCP 1521 Structured Query Language is an interface to access
data on many different types of database systems,
including mainframes, midrange systems, UNIX
systems and network servers.
SSDP UDP 1900 The Simple Service Discovery Protocol supports
Universal Plug-and-Play (UPnP).
SSH TCP/UDP 22 Secure Shell Remote Login Program.
STRM WORKS UDP 1558 Stream Works Protocol.
SYSLOG UDP 514 Syslog allows you to send system logs to a UNIX server.
Table 128 Examples of Services (continued)
NAME PROTOCOL PORT(S) DESCRIPTION
Appendix D Services
VMG3312-T20A User’s Guide
290
TACACS UDP 49 Login Host Protocol used for (Terminal Access
Controller Access Control System).
TELNET TCP 23 Telnet is the login and terminal emulation protocol
common on the Internet and in UNIX environments. It
operates over TCP/IP networks. Its primary function is
to allow users to log into remote host systems.
VDOLIVE TCP
UDP
7000
user-
defined
A videoconferencing solution. The UDP port number is
specified in the application.
Table 128 Examples of Services (continued)
NAME PROTOCOL PORT(S) DESCRIPTION
VMG3312-T20A User’s Guide
291
APPENDIX E
Legal Information
Copyright
Copyright © 2017 by Zyxel Communications Corporation.
The contents of this publication may not be reproduced in any part or as a whole, transcribed, stored in a retrieval system, translated into any
language, or transmitted in any form or by any means, electronic, mechanical, magnetic, optical, chemical, photocopying, manual, or
otherwise, without the prior written permission of Zyxel Communications Corporation.
Published by Zyxel Communications Corporation. All rights reserved.
Disclaimer
Zyxel does not assume any liability arising out of the application or use of any products, or software described herein. Neither does it convey any
license under its patent rights nor the patent rights of others. Zyxel further reserves the right to make changes in any products described herein
without notice. This publication is subject to change without notice.
Regulatory Notice and Statement
UNITED STATES of AMERICA
The following information applies if you use the product within USA area.
FCC EMC Statement
• The device complies with Part 15 of FCC rules. Operation is subject to the following two conditions:
(1) This device may not cause harmful interference, and
(2) This device must accept any interference received, including interference that may cause undesired operation.
• Changes or modifications not expressly approved by the party responsible for compliance could void the user’s authority to operate the
device.
• This product has been tested and complies with the specifications for a Class B digital device, pursuant to Part 15 of the FCC Rules. These
limits are designed to provide reasonable protection against harmful interference in a residential installation. This device generates, uses, and
can radiate radio frequency energy and, if not installed and used according to the instructions, may cause harmful interference to radio
communications. However, there is no guarantee that interference will not occur in a particular installation.
• If this device does cause harmful interference to radio or television reception, which is found by turning the device off and on, the user is
encouraged to try to correct the interference by one or more of the following measures:
• Reorient or relocate the receiving antenna
• Increase the separation between the devices
• Connect the equipment to an outlet other than the receiver’s
• Consult a dealer or an experienced radio/TV technician for assistance
The following information applies if you use the product with RF function within USA area.
FCC Radiation Exposure Statement
• This device complies with FCC RF radiation exposure limits set forth for an uncontrolled environment.
• This transmitter must be at least 20 cm from the user and must not be co-located or operating in conjunction with any other antenna or
transmitter.
CANADA
The following information applies if you use the product within Canada area.
Industry Canada ICES statement
CAN ICES-3 (B)/NMB-3(B)
Industry Canada RSS-GEN & RSS-247 statement
• This device complies with Industry Canada license-exempt RSS standard(s). Operation is subject to the following two conditions: (1) this
device may not cause interference, and (2) this device must accept any interference, including interference that may cause undesired
operation of the device.
Appendix E Legal Information
VMG3312-T20A User’s Guide
292
• This radio transmitter has been approved by Industry Canada to operate with the antenna types listed below with the maximum permissible
gain and required antenna impedance for each antenna type indicated. Antenna types not included in this list, having a gain greater than
the maximum gain indicated for that type, are strictly prohibited for use with this device.
If the product with 5G wireless function operating in 5150-5250 MHz and 5725-5850 MHz , the following attention must be paid,
• The device for operation in the band 5150-5250 MHz is only for indoor use to reduce the potential for harmful interference to co-channel
mobile satellite systems.
• For devices with detachable antenna(s), the maximum antenna gain permitted for devices in the band 5725-5850 MHz shall be such that the
equipment still complies with the e.i.r.p. limits specified for point-to-point and non-point-to-point operation as appropriate; and
• The worst-case tilt angle(s) necessary to remain compliant with the e.i.r.p. elevation mask requirement set forth in Section 6.2.2(3) of RSS 247
shall be clearly indicated.
If the product with 5G wireless function operating in 5250-5350 MHz and 5470-5725 MHz , the following attention must be paid.
• For devices with detachable antenna(s), the maximum antenna gain permitted for devices in the bands 5250-5350 MHz and 5470-5725 MHz
shall be such that the equipment still complies with the e.i.r.p. limit.
• Le présent appareil est conforme aux CNR d’Industrie Canada applicables aux appareils radio exempts de licence. L’exploitation est
autorisée aux deux conditions suivantes : (1) l’appareil ne doit pas produire de brouillage, et (2) l’utilisateur de l’appareil doit accepter tout
brouillage radioélectrique subi, même si le brouillage est susceptible d’en compromettre le fonctionnement.
• Le présent émetteur radio de modèle s'il fait partie du matériel de catégorieI) a été approuvé par Industrie Canada pour fonctionner avec
les types d'antenne énumérés ci-dessous et ayant un gain admissible maximal et l'impédance requise pour chaque type d'antenne. Les
types d'antenne non inclus dans cette liste, ou dont le gain est supérieur au gain maximal indiqué, sont strictement interdits pour l'exploitation
de l'émetteur.
Lorsque la fonction sans fil 5G fonctionnant en 5150-5250 MHz and 5725-5850 MHz est activée pour ce produit , il est nécessaire de porter une
attention particulière aux choses suivantes
• Les dispositifs fonctionnant dans la bande 5150-5250 MHz sont réservés uniquement pour une utilisation à l’intérieur afin de réduire les risques
de brouillage préjudiciable aux systèmes de satellites mobiles utilisant les mêmes canaux;
• Pour les dispositifs munis d’antennes amovibles, le gain maximal d'antenne permis (pour les dispositifs utilisant la bande de 5 725 à 5 850 MHz)
doit être conforme à la limite de la p.i.r.e. spécifiée pour l'exploitation point à point et l’exploitation non point à point, selon le cas;
• Les pires angles d’inclinaison nécessaires pour rester conforme à l’exigence de la p.i.r.e. applicable au masque d’élévation, et énoncée à la
section 6.2.2 3) du CNR-247, doivent être clairement indiqués.
Lorsque la fonction sans fil 5G fonctionnant en 5250-5350 MHz et 5470-5725 MHz est activée pour ce produit , il est nécessaire de porter une
attention particulière aux choses suivantes.
• Pour les dispositifs munis d’antennes amovibles, le gain maximal d'antenne permis pour les dispositifs utilisant les bandes de 5 250 à 5 350 MHz
et de 5 470 à 5 725 MHz doit être conforme à la limite de la p.i.r.e.
Industry Canada radiation exposure statement
This device complies with IC radiation exposure limits set forth for an uncontrolled environment. This device should be installed and operated
with a minimum distance of 20 cm between the radiator and your body.
Déclaration d’exposition aux radiations:
Cet équipement est conforme aux limites d’exposition aux rayonnements IC établies pour un environnement non contrôlé. Cet équipement doit
être installé et utilisé avec un minimum de 20 cm de distance entre la source de rayonnement et votre corps.
EUROPEA N UNION
The following information applies if you use the product within the European Union.
Declaration of Conformity with Regard to EU Directive 1999/5/EC (R&TTE Directive)
• Compliance information for 2.4GHz and/or 5GHz wireless products relevant to the EU and other Countries following the EU Directive 1999/5/
EC (R&TTE).
• This device is restricted to indoor use only when operating in the 5150 to 5350 MHz frequency range.
Български
(Bulgarian)
С настоящото Zyxel декларира, че това оборудване е в съответствие със съществените изисквания и другите
приложими разпоредбите на Директива 1999/5/ЕC.
Español
(Spanish)
Por medio de la presente Zyxel declara que el equipo cumple con los requisitos esenciales y cualesquiera otras
disposiciones aplicables o exigibles de la Directiva 1999/5/CE.
Čeština
(Czech)
Zyxel tímto prohlašuje, že tento zařízení je ve shodě se základními požadavky a dalšími příslušnými ustanoveními směrnice
1999/5/EC.
Dansk (Danish) Undertegnede Zyxel erklærer herved, at følgende udstyr udstyr overholder de væsentlige krav og øvrige relevante krav i
direktiv 1999/5/EF.
Deutsch
(German)
Hiermit erklärt Zyxel, dass sich das Gerät Ausstattung in Übereinstimmung mit den grundlegenden Anforderungen und den
übrigen einschlägigen Bestimmungen der Richtlinie 1999/5/EU befindet.
Eesti keel
(Estonian)
Käesolevaga kinnitab Zyxel seadme seadmed vastavust direktiivi 1999/5/EÜ põhinõuetele ja nimetatud direktiivist
tulenevatele teistele asjakohastele sätetele.
Ελληνικά
(Greek)
ΜΕ ΤΗΝ ΠΑΡΟΥΣΑ Zyxel ∆ΗΛΩΝΕΙ ΟΤΙ εξοπλισμός ΣΥΜΜΟΡΦΩΝΕΤΑΙ ΠΡΟΣ ΤΙΣ ΟΥΣΙΩ∆ΕΙΣ ΑΠΑΙΤΗΣΕΙΣ ΚΑΙ ΤΙΣ ΛΟΙΠΕΣ ΣΧΕΤΙΚΕΣ
∆ΙΑΤΑΞΕΙΣ ΤΗΣ Ο∆ΗΓΙΑΣ 1999/5/ΕC.
Appendix E Legal Information
VMG3312-T20A User’s Guide
293
National Restrictions
• This product may be used in all EU countries (and other countries following the EU Directive 1999/5/EC) without any limitation except for the
countries mentioned below:
• Ce produit peut être utilisé dans tous les pays de l’UE (et dans tous les pays ayant transposés la directive 1999/5/CE) sans aucune limitation,
excepté pour les pays mentionnés ci-dessous:
• Questo prodotto è utilizzabile in tutte i paesi EU (ed in tutti gli altri paesi che seguono le direttiva 1999/5/EC) senza nessuna limitazione,
eccetto per i paesii menzionati di seguito:
• Das Produkt kann in allen EU Staaten ohne Einschränkungen eingesetzt werden (sowie in anderen Staaten die der Richtlinie 1999/5/CE
folgen) mit Außnahme der folgenden aufgeführten Staaten:
In the majority of the EU and other European countries, the 2.4GHz and 5GHz bands have been made available for the use of wireless local area
networks (LANs). Later in this document you will find an overview of countries in which additional restrictions or requirements or both are
applicable. The requirements for any country may evolve. Zyxel recommends that you check with the local authorities for the latest status of
their national regulations for both the 2.4GHz and 5GHz wireless LANs. The following countries have restrictions and/or requirements in addition to
those given in the table labeled “Overview of Regulatory Requirements for Wireless LANs”:.
Belgium
• The Belgian Institute for Postal Services and Telecommunications (BIPT) must be notified of any outdoor wireless link having a range
exceeding 300 meters. Please check http://www.bipt.be for more details.
• Draadloze verbindingen voor buitengebruik en met een reikwijdte van meer dan 300 meter dienen aangemeld te worden bij het Belgisch
Instituut voor postdiensten en telecommunicatie (BIPT). Zie http://www.bipt.be voor meer gegevens.
• Les liaisons sans fil pour une utilisation en extérieur d’une distance supérieure à 300 mètres doivent être notifiées à l’Institut Belge des services
Postaux et des Télécommunications (IBPT). Visitez http://www.ibpt.be pour de plus amples détails.
Denmark
• In Denmark, the band 5150 - 5350 MHz is also allowed for outdoor usage.
• I Danmark må frekvensbåndet 5150 - 5350 også anvendes udendørs.
Italy
• This product meets the National Radio Interface and the requirements specified in the National Frequency Allocation Table for Italy. Unless
this wireless LAN product is operating within the boundaries of the owner's property, its use requires a “general authorization.” Please check
http://www.sviluppoeconomico.gov.it/ for more details.
English Hereby, Zyxel declares that this device is in compliance with the essential requirements and other relevant provisions of
Directive 1999/5/EC.
Français
(French)
Par la présente Zyxel déclare que l'appareil équipements est conforme aux exigences essentielles et aux autres dispositions
pertinentes de la directive 1999/5/EC.
Hrvatski
(Croatian)
Zyxel ovime izjavljuje da je radijska oprema tipa u skladu s Direktivom 1999/5/EC.
Íslenska
(Icelandic)
Hér með lýsir, Zyxel því yfir að þessi búnaður er í samræmi við grunnkröfur og önnur viðeigandi ákvæði tilskipunar 1999/5/EC.
Italiano (Italian) Con la presente Zyxel dichiara che questo attrezzatura è conforme ai requisiti essenziali ed alle altre disposizioni pertinenti
stabilite dalla direttiva 1999/5/CE.
Latviešu valoda
(Latvian)
Ar šo Zyxel deklarē, ka iekārtas atbilst Direktīvas 1999/5/EK būtiskajām prasībām un citiem ar to saistītajiem noteikumiem.
Lietuvių kalba
(Lithuanian)
Šiuo Zyxel deklaruoja, kad šis įranga atitinka esminius reikalavimus ir kitas 1999/5/EB Direktyvos nuostatas.
Magyar
(Hungarian)
Alulírott, Zyxel nyilatkozom, hogy a berendezés megfelel a vonatkozó alapvetõ követelményeknek és az 1999/5/EK irányelv
egyéb elõírásainak.
Malti (Maltese) Hawnhekk, Zyxel, jiddikjara li dan tagħmir jikkonforma mal-ħtiġijiet essenzjali u ma provvedimenti oħrajn relevanti li hemm
fid-Dirrettiva 1999/5/EC.
Nederlands
(Dutch)
Hierbij verklaart Zyxel dat het toestel uitrusting in overeenstemming is met de essentiële eisen en de andere relevante
bepalingen van richtlijn 1999/5/EC.
Polski (Polish) Niniejszym Zyxel oświadcza, że sprzęt jest zgodny z zasadniczymi wymogami oraz pozostałymi stosownymi postanowieniami
Dyrektywy 1999/5/EC.
Português
(Portuguese)
Zyxel declara que este equipamento está conforme com os requisitos essenciais e outras disposições da Directiva 1999/5/
EC.
Română
(Romanian)
Prin prezenta, Zyxel declară că acest echipament este în conformitate cu cerinţele esenţiale şi alte prevederi relevante ale
Directivei 1999/5/EC.
Slovenčina
(Slovak)
Zyxel týmto vyhlasuje, že zariadenia spĺňa základné požiadavky a všetky príslušné ustanovenia Smernice 1999/5/EC.
Slovenščina
(Slovene)
Zyxel izjavlja, da je ta oprema v skladu z bistvenimi zahtevami in ostalimi relevantnimi določili direktive 1999/5/EC.
Suomi (Finnish) Zyxel vakuuttaa täten että laitteet tyyppinen laite on direktiivin 1999/5/EY oleellisten vaatimusten ja sitä koskevien direktiivin
muiden ehtojen mukainen.
Svenska
(Swedish)
Härmed intygar Zyxel att denna utrustning står I överensstämmelse med de väsentliga egenskapskrav och övriga relevanta
bestämmelser som framgår av direktiv 1999/5/EC.
Norsk
(Norwegian)
Erklærer herved Zyxel at dette utstyret er I samsvar med de grunnleggende kravene og andre relevante bestemmelser I
direktiv 1999/5/EF.
Appendix E Legal Information
VMG3312-T20A User’s Guide
294
• Questo prodotto è conforme alla specifiche di Interfaccia Radio Nazionali e rispetta il Piano Nazionale di ripartizione delle frequenze in Italia.
Se non viene installato all 'interno del proprio fondo, l'utilizzo di prodotti Wireless LAN richiede una “Autorizzazione Generale”. Consultare
http://www.sviluppoeconomico.gov.it/ per maggiori dettagli.
Latvia
• The outdoor usage of the 2.4 GHz band requires an authorization from the Electronic Communications Office. Please check http://
www.esd.lv for more details.
• 2.4 GHz frekvenèu joslas izmantoðanai ârpus telpâm nepiecieðama atïauja no Elektronisko sakaru direkcijas. Vairâk informâcijas: http://
www.esd.lv.
Notes:
1. Although Norway, Switzerland and Liechtenstein are not EU member states, the EU Directive 1999/5/EC has also been implemented in
those countries.
2. The regulatory limits for maximum output power are specified in EIRP. The EIRP level (in dBm) of a device can be calculated by adding the
gain of the antenna used(specified in dBi) to the output power available at the connector (specified in dBm).
List of national codes
Safety Warnings
• Do not use this product near water, for example, in a wet basement or near a swimming pool.
• Do not expose your device to dampness, dust or corrosive liquids.
• Do not store things on the device.
• Do not obstruct the device ventilation slots as insufficient airflow may harm your device. For example, do not place the device in an
enclosed space such as a box or on a very soft surface such as a bed or sofa.
• Do not install, use, or service this device during a thunderstorm. There is a remote risk of electric shock from lightning.
• Connect ONLY suitable accessories to the device.
• Do not open the device or unit. Opening or removing covers can expose you to dangerous high voltage points or other risks. ONLY qualified
service personnel should service or disassemble this device. Please contact your vendor for further information.
• Make sure to connect the cables to the correct ports.
• Place connecting cables carefully so that no one will step on them or stumble over them.
• Always disconnect all cables from this device before servicing or disassembling.
• Do not remove the plug and connect it to a power outlet by itself; always attach the plug to the power adaptor first before connecting it to
a power outlet.
• Do not allow anything to rest on the power adaptor or cord and do NOT place the product where anyone can walk on the power adaptor
or cord.
• Please use the provided or designated connection cables/power cables/ adaptors. Connect it to the right supply voltage (for example,
110V AC in North America or 230V AC in Europe). If the power adaptor or cord is damaged, it might cause electrocution. Remove it from the
device and the power source, repairing the power adapter or cord is prohibited. Contact your local vendor to order a new one.
• Do not use the device outside, and make sure all the connections are indoors. There is a remote risk of electric shock from lightning.
• CAUTION: Risk of explosion if battery is replaced by an incorrect type, dispose of used batteries according to the instruction. Dispose them at
the applicable collection point for the recycling of electrical and electronic devices. For detailed information about recycling of this
product, please contact your local city office, your household waste disposal service or the store where you purchased the product.
• The following warning statements apply, where the disconnect device is not incorporated in the device or where the plug on the power
supply cord is intended to serve as the disconnect device,
- For permanently connected devices, a readily accessible disconnect device shall be incorporated external to the device;
- For pluggable devices, the socket-outlet shall be installed near the device and shall be easily accessible.
COUNTRY ISO 3166 2 LETTER CODE COUNTRY ISO 3166 2 LETTER CODE
Austria AT Liechtenstein LI
Belgium BE Lithuania LT
Bulgaria BG Luxembourg LU
Croatia HR Malta MT
Cyprus CY Netherlands NL
Czech Republic CZ Norway NO
Denmark DK Poland PL
Estonia EE Portugal PT
Finland FI Romania RO
France FR Serbia RS
Germany DE Slovakia SK
Greece GR Slovenia SI
Hungary HU Spain ES
Iceland IS Switzerland CH
Ireland IE Sweden SE
Italy IT Turkey TR
Latvia LV United Kingdom GB
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Environment Statement
ErP (Energy-related Products)
Zyxel products put on the EU market in compliance with the requirement of the European Parliament and the Council published Directive 2009/
125/EC establishing a framework for the setting of ecodesign requirements for energy-related products (recast), so called as "ErP Directive
(Energy-related Products directive) as well as ecodesign requirement laid down in applicable implementing measures, power consumption has
satisfied regulation requirements which are:
• Network standby power consumption < 8W, and/or
• Off mode power consumption < 0.5W, and/or
• Standby mode power consumption < 0.5W.
(Wireless setting, please refer to "Wireless" chapter for more detail.)
European Union - Disposal and Recycling Information
The symbol below means that according to local regulations your product and/or its battery shall be disposed of separately from domestic
waste. If this product is end of life, take it to a recycling station designated by local authorities. At the time of disposal, the separate collection of
your product and/or its battery will help save natural resources and ensure that the environment is sustainable development.
Die folgende Symbol bedeutet, dass Ihr Produkt und/oder seine Batterie gemäß den örtlichen Bestimmungen getrennt vom Hausmüll entsorgt
werden muss. Wenden Sie sich an eine Recyclingstation, wenn dieses Produkt das Ende seiner Lebensdauer erreicht hat. Zum Zeitpunkt der
Entsorgung wird die getrennte Sammlung von Produkt und/oder seiner Batterie dazu beitragen, natürliche Ressourcen zu sparen und die Umwelt
und die menschliche Gesundheit zu schützen.
El símbolo de abajo indica que según las regulaciones locales, su producto y/o su batería deberán depositarse como basura separada de la
doméstica. Cuando este producto alcance el final de su vida útil, llévelo a un punto limpio. Cuando llegue el momento de desechar el
producto, la recogida por separado éste y/o su batería ayudará a salvar los recursos naturales y a proteger la salud humana y
medioambiental.
Le symbole ci-dessous signifie que selon les réglementations locales votre produit et/ou sa batterie doivent être éliminés séparément des ordures
ménagères. Lorsque ce produit atteint sa fin de vie, amenez-le à un centre de recyclage. Au moment de la mise au rebut, la collecte séparée
de votre produit et/ou de sa batterie aidera à économiser les ressources naturelles et protéger l'environnement et la santé humaine.
Il simbolo sotto significa che secondo i regolamenti locali il vostro prodotto e/o batteria deve essere smaltito separatamente dai rifiuti domestici.
Quando questo prodotto raggiunge la fine della vita di servizio portarlo a una stazione di riciclaggio. Al momento dello smaltimento, la raccolta
separata del vostro prodotto e/o della sua batteria aiuta a risparmiare risorse naturali e a proteggere l'ambiente e la salute umana.
Symbolen innebär att enligt lokal lagstiftning ska produkten och/eller dess batteri kastas separat från hushållsavfallet. När den här produkten når
slutet av sin livslängd ska du ta den till en återvinningsstation. Vid tiden för kasseringen bidrar du till en bättre miljö och mänsklig hälsa genom att
göra dig av med den på ett återvinningsställe.
Appendix E Legal Information
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Environmental Product Declaration
Appendix E Legal Information
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台灣
以下訊息僅適用於產品具有無線功能且銷售至台灣地區
• 第十二條 經型式認證合格之低功率射頻電機，非經許可，公司，商號或使用者均不得擅自變更頻率、加大功率或變更原設計之特性及功能。
• 第十四條 低功率射頻電機之使用不得影響飛航安全及干擾合法通信；經發現有干擾現象時，應立即停用，並改善至無干擾時方得繼續使用。
前項合法通信，指依電信法規定作業之無線電通信。 低功率射頻電機須忍受合法通信或工業、科學及醫療用電波輻射性電機設備之干擾。
• 無線資訊傳輸設備忍受合法通信之干擾且不得干擾合法通信；如造成干擾，應立即停用， 俟無干擾之虞，始得繼續使用。
• 無線資訊傳設備的製造廠商應確保頻率穩定性，如依製造廠商使用手冊上所述正常操作， 發射的信號應維持於操作頻帶中
以下訊息僅適用於產品操作於 5.25-5.35 秭赫頻帶內並銷售至台灣地區
• 在 5.25-5.35 秭赫頻帶內操作之無線資訊傳輸設備，限於室內使用。
以下訊息僅適用於產品屬於專業安裝並銷售至台灣地區
• 本器材須經專業工程人員安裝及設定，始得設置使用，且不得直接販售給一般消費者。
安全警告 - 為了您的安全，請先閱讀以下警告及指示 :
• 請勿將此產品接近水、火焰或放置在高溫的環境。
• 避免設備接觸 :
- 任何液體 - 切勿讓設備接觸水、雨水、高濕度、污水腐蝕性的液體或其他水份。
- 灰塵及污物 - 切勿接觸灰塵、污物、沙土、食物或其他不合適的材料。
• 雷雨天氣時，不要安裝，使用或維修此設備。有遭受電擊的風險。
• 切勿重摔或撞擊設備，並勿使用不正確的電源變壓器。
• 若接上不正確的電源變壓器會有爆炸的風險。
• 請勿隨意更換產品內的電池。
• 如果更換不正確之電池型式，會有爆炸的風險，請依製造商說明書處理使用過之電池。
• 請將廢電池丟棄在適當的電器或電子設備回收處。
• 請勿將設備解體。
• 請勿阻礙設備的散熱孔，空氣對流不足將會造成設備損害。
• 請插在正確的電壓供給插座 ( 如 : 北美 / 台灣電壓 110V AC，歐洲是 230V AC)。
• 假若電源變壓器或電源變壓器的纜線損壞，請從插座拔除，若您還繼續插電使用，會有觸電死亡的風險。
• 請勿試圖修理電源變壓器或電源變壓器的纜線，若有毀損，請直接聯絡您購買的店家，購買一個新的電源變壓器。
• 請勿將此設備安裝於室外，此設備僅適合放置於室內。
• 請勿隨一般垃圾丟棄。
• 請參閱產品背貼上的設備額定功率。
• 請參考產品型錄或是彩盒上的作業溫度。
• 產品沒有斷電裝置或者採用電源線的插頭視為斷電裝置的一部分，以下警語將適用 :
- 對永久連接之設備， 在設備外部須安裝可觸及之斷電裝置；
- 對插接式之設備， 插座必須接近安裝之地點而且是易於觸及的。
About the Symbols
Various symbols are used in this product to ensure correct usage, to prevent danger to the user and others, and to prevent property damage.
The meaning of these symbols are described below. It is important that you read these descriptions thoroughly and fully understand the
contents.
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Explanation of the Symbols
Viewing Certifications
Go to http://www.zyxel.com to view this product’s documentation and certifications.
Zyxel Limited Warranty
Zyxel warrants to the original end user (purchaser) that this product is free from any defects in material or workmanship for a specific period (the
Warranty Period) from the date of purchase. The Warranty Period varies by region. Check with your vendor and/or the authorized Zyxel local
distributor for details about the Warranty Period of this product. During the warranty period, and upon proof of purchase, should the product
have indications of failure due to faulty workmanship and/or materials, Zyxel will, at its discretion, repair or replace the defective products or
components without charge for either parts or labor, and to whatever extent it shall deem necessary to restore the product or components to
proper operating condition. Any replacement will consist of a new or re-manufactured functionally equivalent product of equal or higher value,
and will be solely at the discretion of Zyxel. This warranty shall not apply if the product has been modified, misused, tampered with, damaged by
an act of God, or subjected to abnormal working conditions.
Note
Repair or replacement, as provided under this warranty, is the exclusive remedy of the purchaser. This warranty is in lieu of all other warranties,
express or implied, including any implied warranty of merchantability or fitness for a particular use or purpose. Zyxel shall in no event be held
liable for indirect or consequential damages of any kind to the purchaser.
To obtain the services of this warranty, contact your vendor. You may also refer to the warranty policy for the region in which you bought the
device at http://www.zyxel.com/web/support_warranty_info.php.
Registration
Register your product online to receive e-mail notices of firmware upgrades and information at www.zyxel.com for global products, or at
www.us.zyxel.com for North American products.
Open Source Licenses
This product contains in part some free software distributed under GPL license terms and/or GPL like licenses. Open source licenses are provided
with the firmware package. You can download the latest firmware at www.zyxel.com. To obtain the source code covered under those Licenses,
please contact support@zyxel.com.tw to get it.
SYMBOL EXPLANATION
Alternating current (AC):
AC is an electric current in which the flow of electric charge periodically reverses direction.
Direct current (DC):
DC if the unidirectional flow or movement of electric charge carriers.
Earth; ground:
A wiring terminal intended for connection of a Protective Earthing Conductor.
Class II equipment:
The method of protection against electric shock in the case of class II equipment is either double insulation or
reinforced insulation.
Index
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Index
A
ACL rule 197
activation
firewalls 194
media server 192
SIP ALG 172
SSID 102
Address Resolution Protocol 222
administrator password 26
antenna
directional 278
gain 277
omni-directional 278
AP (access point) 268
applications
Internet access 16
media server 192
activation 192
iTunes server 192
applications, NAT 176
ARP Table 222, 224
authentication 112, 113
RADIUS server 113
B
backup
configuration 248
Basic Service Set, See BSS 266
Basic Service Set, see BSS
blinking LEDs 20
Broadband 70
broadcast 94
BSS 115, 266
example 115
C
CA 209, 272
Canonical Format Indicator See CFI
CCMs 251
certificate
factory default 210
Certificate Authority
See CA.
certificates 209
authentication 209
CA
creating 210
public key 209
replacing 210
storage space 210
Certification Authority 209
Certification Authority. see CA
certifications 294
viewing 298
CFI 94
CFM 251
CCMs 251
link trace test 251
loopback test 251
MA 251
MD 251
MEP 251
MIP 251
channel 268
interference 268
channel, wireless LAN 111
client list 129
configuration
backup 248
firewalls 194
reset 249
restoring 249
static route 139, 141, 180
Connectivity Check Messages, see CCMs
contact information 260
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copyright 291
CoS 159
CoS technologies 146
creating certificates 210
CTS (Clear to Send) 269
CTS threshold 108, 112
customer support 260
D
data fragment threshold 108, 112
DDoS 194
default server address 171
Denials of Service, see DoS
DHCP 124, 136
Differentiated Services, see DiffServ 159
DiffServ 159
marking rule 159
digital IDs 209
disclaimer 291
DLNA 192
DMZ 171
DNS 124, 136
DNS server address assignment 95
Domain Name 177
Domain Name System, see DNS
Domain Name System. See DNS.
DoS 194
DS field 159
DS, dee differentiated services
DSCP 159
dynamic DNS 179
wildcard 179
Dynamic Host Configuration Protocol, see DHCP
dynamic WEP key exchange 273
DYNDNS wildcard 179
E
EAP Authentication 272
ECHO 177
e-mail
log example 244
Encapsulation 91
MER 91
PPP over Ethernet 91
encapsulation
RFC 1483 92
encryption 114, 274
ESS 267
Extended Service Set IDentification 98, 103
Extended Service Set, See ESS 267
F
file sharing 18
filters
MAC address 113
Finger 177
firewalls 193
add protocols 195
configuration 194
DDoS 194
DoS 194
LAND attack 194
Ping of Death 194
SYN attack 194
firmware 246
version 68
forwarding ports 164
fragmentation threshold 108, 112, 269
FTP 164, 177
G
General wireless LAN screen 97
H
hidden node 268
HTTP 177
Index
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I
IBSS 266
IEEE 802.11g 270
IEEE 802.1Q 94
IGA 175
IGMP 95
version 95
ILA 175
Independent Basic Service Set
See IBSS 266
initialization vector (IV) 274
Inside Global Address, see IGA
Inside Local Address, see ILA
interface group 183
Internet
wizard setup 33
Internet access 16
wizard setup 33
Internet Protocol version 6 71
Internet Protocol version 6, see IPv6
IP address 124, 137
ping 252
private 137
WAN 71
IP Address Assignment 94
IP alias
NAT applications 177
IPv6 71, 279
addressing 72, 95, 279
EUI-64 281
global address 279
interface ID 281
link-local address 279
Neighbor Discovery Protocol 279
ping 279
prefix 72, 95, 279
prefix delegation 74
prefix length 72, 95, 279
unspecified address 280
iTunes server 192
L
LAN 123
client list 129
DHCP 124, 136
DNS 124, 136
IP address 124, 125, 137
MAC address 129
status 68
subnet mask 124, 125, 137
LAND attack 194
LBR 251
limitations
wireless LAN 114
WPS 121
link trace 251
Link Trace Message, see LTM
Link Trace Response, see LTR
login 26
passwords 26
logs 216, 219, 228, 243
Loop Back Response, see LBR
loopback 251
LTM 251
LTR 251
M
MA 251
MAC address 129
filter 113
Mac filter 200
Maintenance Association, see MA
Maintenance Domain, see MD
Maintenance End Point, see MEP
Management Information Base (MIB) 237
managing the device
good habits 15
Maximum Burst Size (MBS) 92
MBSSID 115
MD 251
media server 192
activation 192
iTunes server 192
MEP 251
MTU (Multi-Tenant Unit) 94
multicast 94
Index
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Multiple BSS, see MBSSID
multiplexing 92
LLC-based 92
VC-based 92
multiprotocol encapsulation 92
N
NAT 163, 164, 165, 175, 176
applications 176
IP alias 177
example 176
global 175
IGA 175
ILA 175
inside 175
local 175
outside 175
port forwarding 164
port number 177
services 177
SIP ALG 172
activation 172
NAT example 178
Network Address Translation, see NAT
Network Map 66
network map 29
NNTP 177
P
Pairwise Master Key (PMK) 274, 276
passwords 26
PBC 116
Peak Cell Rate (PCR) 92
Per-Hop Behavior, see PHB 159
PHB 159
PIN, WPS 117
Ping of Death 194
Point-to-Point Tunneling Protocol, see PPTP
POP3 177
port forwarding 164
ports 20
PPPoE 91
Benefits 91
PPTP 177
preamble 109, 112
preamble mode 116
prefix delegation 74
private IP address 137
PSK 274
push button 23
Push Button Configuration, see PBC
push button, WPS 116
Q
QoS 145, 159
marking 146
setup 145
tagging 146
versus CoS 146
Quality of Service, see QoS
R
RADIUS 271
message types 271
messages 271
shared secret key 272
RADIUS server 113
reset 24, 249
restart 250
restoring configuration 249
RFC 1058. See RIP.
RFC 1389. See RIP.
RFC 1483 92
RFC 3164 216
RIP 143
router features 16
Routing Information Protocol. See RIP
RTS (Request To Send) 269
threshold 268, 269
RTS threshold 108, 112
Index
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S
security
wireless LAN 112
Security Log 217
Security Parameter Index, see SPI
service access control 234, 235
Service Set 98, 103
Services 177
setup
firewalls 194
static route 139, 141, 180
Simple Network Management Protocol, see SNMP
Single Rate Three Color Marker, see srTCM
SIP ALG 172
activation 172
SMTP 177
SNMP 177, 237, 238
agents 237
Get 238
GetNext 238
Manager 237
managers 237
MIB 237
network components 237
Set 238
Trap 238
versions 237
SNMP trap 177
SPI 194
srTCM 161
SSID 113
activation 102
MBSSID 115
static route 138, 143, 241
configuration 139, 141, 180
example 138
static VLAN
status 66
firmware version 68
LAN 68
WAN 68
wireless LAN 68
status indicators 20
subnet mask 124, 137
Sustained Cell Rate (SCR) 92
SYN attack 194
syslog
protocol 216
severity levels 216
system
firmware 246
version 68
passwords 26
reset 24
status 66
LAN 68
WAN 68
wireless LAN 68
time 239
T
Tag Control Information See TCI
Tag Protocol Identifier See TPID
TCI
The 71
thresholds
data fragment 108, 112
RTS/CTS 108, 112
time 239
TPID 94
traffic shaping 92
trTCM 161
Two Rate Three Color Marker, see trTCM
U
unicast 94
Universal Plug and Play, see UPnP
upgrading firmware 246
UPnP 130
cautions 125
NAT traversal 124
USB features 18
Index
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V
Vendor ID 134
VID
Virtual Circuit (VC) 92
Virtual Local Area Network See VLAN
VLAN 94
Introduction 94
number of possible VIDs
priority frame
static
VLAN ID 94
VLAN Identifier See VID
VLAN tag 94
W
Wake on LAN 134
WAN
status 68
Wide Area Network, see WAN 70
warranty 298
note 298
web configurator 26
login 26
passwords 26
WEP 114
WEP Encryption 100, 101
WEP encryption 99
WEP key 99
Wi-Fi Protected Access 273
wireless client WPA supplicants 275
wireless LAN 96, 110
authentication 112, 113
BSS 115
example 115
channel 111
encryption 114
example 111
fragmentation threshold 108, 112
limitations 114
MAC address filter 113
MBSSID 115
preamble 109, 112
RADIUS server 113
RTS/CTS threshold 108, 112
security 112
SSID 113
activation 102
status 68
WEP 114
WPA 114
WPA-PSK 114
WPS 116, 118
example 119
limitations 121
PIN 117
push button 23, 116
wireless security 270
Wireless tutorial 41
wizard setup
Internet 33
WLAN
interference 268
security parameters 277
WPA 114, 273
key caching 275
pre-authentication 275
user authentication 274
vs WPA-PSK 274
wireless client supplicant 275
with RADIUS application example 275
WPA2 273
user authentication 274
vs WPA2-PSK 274
wireless client supplicant 275
with RADIUS application example 275
WPA2-Pre-Shared Key 273
WPA2-PSK 273, 274
application example 276
WPA-PSK 114, 274
application example 276
WPS 116, 118
example 119
limitations 121
PIN 117
push button 23, 116
Z
ZyXEL Family Safety page 205